MATH NEWS ARCHIVE


February 2007
a cura di Umberto Cerruti -- Math News Archive -- Home
Please send me any news about mathematics, mathematical models and mathematicians! Write "mathnews" in the object.

February 27, 2007

Medieval Islamic tiling reveals mathematical savvy

www.newscientist.com
Girih pattern (Image: Science)
Girih pattern from the
Seljuk Mama Hatun Mausoleum in Tercan,
Turkey (about AD 1200),
with girih-tile reconstruction overlaid at bottom
(Image: Science)
19:00 22 February 2007
NewScientist.com news service
Jeff Hecht

Medieval Islamic designers used elaborate geometrical tiling patterns at least 500 years before Western mathematicians developed the concept.
The geometric design, called "girih", was widely used to decorate Islamic buildings but the advanced mathematical concept within the patterns was not recognised, until now. Physicist Peter Lu at Harvard University in Cambridge, Massachusetts, US, realised the 15th-century tiles formed so-called Penrose geometric patterns, when he spotted them on a visit to Uzbekistan.
Scholars had thought the girih were created by drawing a zigzag network of lines with a straight edge and compass. But when Lu looked at them, he recognised the regular but non-repetitive patterns of Penrose tiling - a concept developed in the West only in the 1970s.
Simple periodic patterns can be generated easily by repeating a unit cell of several elements, a technique widely used in tile patterns, but the rotational symmetry possible is limited. In the 1970s, Roger Penrose at the University of Oxford in the UK showed, for the first time, that "thick" and "thin" rhombus-shaped tiles could cover a plane, creating a non-repetitive pattern with five-fold rotational symmetry.
Shapes and sizes
Other researchers found that the atoms in certain materials can arrange themselves in similar non-repetitive patterns, which are called quasi-crystals. They are called this because they have a well-defined structure but the atoms are not spaced uniformly as in a normal crystal.
Lu discovered a wealth of girih designs with quasi-crystal patterns through an archive search of documented medieval Islamic architecture. He also found architectural scrolls describing how girih designs were assembled from five regularly shaped tiles, including a bowtie shape, a rhombus, a pentagon, an elongated hexagon, and a decagon.
"These are not quite perfect quasi-crystals," he told New Scientist, because the patterns show a few defects where a single tile was placed incorrectly. He suspects the defects were mistakes by workers putting together the design specified by the designer. "It's only 11 defects out of 3700 Penrose tiles, and each can be corrected by a simple rotation," he says.
The set of five girih tiles decorated with lines that fit together to make regular patterns first appeared about 1200 AD, a time when Islamic mathematics was flowering. The designs grew increasingly complex, and by the 15th century produced near-perfect Penrose patterns found on the Darb-i Imam shrine in Isfahan, Iran. Journal reference: Science (vol 315, p 1106)


Medieval Islamic tiling reveals mathematical savvy
February 27, 2007

Study may change view of mathematical origins

www.newsday.com
BY BRYN NELSON
February 22, 2007, 5:03 PM EST

Islamic architects had mastered a sophisticated tile template that allowed them to create a dizzying array of star and polygon decorations more than half a millennium before the concept caught on in the West, according to a new study.
The geometrical know-how of these early Islamic designers, the authors conclude in the journal Science, "led the medieval world" and should force a reappraisal of where important mathematical concepts really originated -- a sentiment echoed by an independent expert who has identified fractal geometry in traditional African culture and who called the new research "absolutely stunning."
Scientists previously believed these medieval Islamic artisans had constructed their complicated motifs with a compass and straightedge. But Harvard University graduate student Peter Lu said that technique is unlikely to explain how designs requiring the piecing together of thousands of tiles with up to ten sides could have been so accurately fit together.
Lu, lead author of the new study, was traveling through central Asia with a cousin volunteering for the Peace Corps when he spotted a familiar pattern on a medieval Islamic building in Uzbekistan: tile work with ten-pointed stars.
As an undergraduate student in the lab of Princeton University physicist Peter Steinhardt, Lu had studied quasi-crystals, or structures based on a type of irregular symmetry that would give professional floor tilers nightmares. Such crystals possess "forbidden symmetry," meaning that five- or ten-sided shapes might look the same when rotated by 36 or 72 degrees but can't be fit snugly together in a repeating pattern without leaving gaps.
In 1974, British mathematical physicist Roger Penrose came up with a two-tile system based on thin and fat rhombus shapes that could finally incorporate the five-fold symmetry into a snug-fitting tile pattern. But Lu's work suggests Islamic architects beat him to the punch by well over 500 years.
With Harvard's extensive library of Islamic architectural examples to guide him, he scrutinized medieval tile work and even Quran adornments featuring five- and ten-pointed stars. Again and again, he found a set of five precisely shaped and decorated tiles could account for the overall designs.
"The big, big picture is that we've discovered -- and I think we've proven rigorously -- that the Islamic architects had a process that would have allowed them to create infinite quasi-crystals," Lu said. "And that's something that we in the West didn't know how to do until the last 30 years."
The advanced knowledge of math and science led to a set of five polygons known as girih tiles. This set, including a rhombus, pentagon, decagon, hexagon, and bow tie-shaped hexagon tile, were all designed to have edges with the same exact length so they could be fit together. Each of the five tiles also featured specific line markings to create embedded geometrical shapes. Furthermore, the angles of the tiles and their intersecting lines were limited to multiples of 36 degrees.
When pieced together, the tile shapes form one geometrical pattern, while their interior lines continue across the tile boundaries to form a separate, zigzagging design.
More than just a theoretical construct, Lu believes sets of girih tiles were being used to trace decorative motifs by 1200 AD, with their adoption spreading across the medieval Islamic world. As proof, he points to a 15th-Century scroll now housed in a museum in Istanbul, Turkey, that contains detailed ink outlines of the five tiles and their lines, and to an "all-star lineup of buildings" in multiple countries whose decorations can be explained by applying the same tile templates.
Prominent adornments on the 13th-Century Abbasid Al-Mustansiriyya Madrasa in Baghdad, 13th-Century Seljuk Mama Hatun Mausoleum in Tercan, Turkey and 15th-Century Seljuk Great Mosque in Narriz, Iran all can be explained by lining up various girih tile combinations into larger patterns.
"The take-home message is that there's a lot more to be learned by looking in this part of the world," Lu said. And if his study motivates other researchers to do just that, "that would be really fantastic."
Ron Eglash, an associate professor of science and technology studies at Rensselaer Polytechnic Institute in Troy, N.Y., agreed, calling the new research "absolutely stunning."
In an e-mail, Eglash hailed Lu's ability to not only analyze the complicated pattern but also demonstrate how Islamic knowledge allowed it to be widely applied.
"That's very important for some of these Islamic societies because they are often looked down on as merely being the 'storehouse' of Western knowledge during the Dark Ages," Eglash said. "Here you have a portrait of them as not only independent innovators, but actually several centuries ahead of the West."
Eglash himself discovered that fractal geometry was widely adopted in traditional African culture long before researchers had assumed such mathematical knowledge arrived from the West. He first identified the use of fractal geometry's similar shapes repeated on ever-shrinking scales in aerial photographs of Tanzanian thatched-roof huts arranged as circular clusters within larger circular clusters. Since then, Eglash has identified the use of fractal geometry in everything from Saharan wind screens to traditional hair braiding and Senegalese fortune telling.
Copyright 2007 Newsday Inc.
Study may change view of mathematical origins

February 27, 2007

UW scientists unlock major number theory puzzle

www.news.wisc.edu
February 26, 2007
by Paroma Basu

Mathematicians have finally laid to rest the legendary mystery surrounding an elusive group of numerical expressions known as the "mock theta functions."
Number theorists have struggled to understand the functions ever since the great Indian mathematician Srinivasa Ramanujan first alluded to them in a letter written on his deathbed, in 1920.
Now, using mathematical techniques that emerged well after Ramanujan's death, two number theorists at the University of Wisconsin-Madison have pieced together an explanatory framework that for the first time illustrates what mock theta functions are, and exactly how to derive them.
Their new theory is proving invaluable in the resolution of long-standing open questions in number theory. In addition, the UW-Madison advance will for the first time enable researchers to apply mock theta functions to problems in a variety of fields, including physics, chemistry and several branches of mathematics. The findings appear in a series of three papers, the third appearing today in the Proceedings of the National Academy of Sciences.
"It's extremely gratifying to be able to say we solved the 'final problem' of Ramanujan," says co-author Ken Ono, UW-Madison Manasse Professor of Letters and Science, who is widely noted for contributions to number theory. "We simply got really lucky."
Ono worked in collaboration with German mathematician Kathrin Bringmann, a postdoctoral researcher at UW-Madison.
"This is something I really didn't expect anybody to do," says George Andrews, a leading number theorist at Pennsylvania State University who in 2000 called mock theta functions one of the most difficult math puzzles of the new millennium. "It is an outstanding piece of work, a breathtakingly wonderful achievement."
Working from Ramanujan's letter, number theorists believed that mock theta functions are related to a well-understood class of mathematical expressions-the 'theta' functions-that have been in use for centuries. Theta functions constitute a certain sequence of numbers that has proved useful in various problems of mathematical analysis.
Mock theta functions similarly constitute an infinite series of numbers. But what has been completely baffling is what it is about mock theta series that make them so rich and powerful. Over the decades-much to the amazement of mathematicians everywhere-mock theta functions have cropped up amidst calculations in a number of fields, including mathematics, physics, chemistry, and even cancer research.
What made mock theta functions all the more inscrutable was the fact that the first few pages of Ramanujan's letter were lost. Those pages may have contained more clues, but in their absence, the letter merely presented 17 examples of the functions. What's missing is any definition of what the functions are, any hints on how to derive them, and any indication of why they are even important. All those secrets died with Ramanujan just two months after he wrote the letter, when he succumbed to tuberculosis at the age of 32.
"Imagine stringing together a thousand random words and then saying you've come up with the most beautiful poetry," says Ono. "That's essentially what Ramanujan did to us."
Bringmann and Ono made sense of it all by finding a way to represent the power of mock theta functions through another relatively new family of mathematical expressions known as the Harmonic Maass Forms.
A Dutch mathematician named Sander Zwegers had already made that important connection in 2002, but he had focused only on Ramanujan's examples.
It was during a flight to New Hampshire that Ono realized the full depth and meaning of Zwegers' work. Skimming a journal to pass the time, Ono happened upon an old article by George Andrews on mock theta functions. Suddenly, he noticed that some of the mathematics in the paper seemed to resonate with parts of the Harmonic Maass theory, which he and Bringmann just happened to be developing at the time, for other reasons.
The mathematicians found the connection held up beautifully. "We knew we were onto something right away," says Ono. "It was an uncanny set of coincidences that lead us to this solution. It was as if it all just fell into our lap and now we are serendipitously applying our theory to longstanding open problems."
UW scientists unlock major number theory puzzle

February 27, 2007

Sloan Research Fellowships awarded to three UC Santa Cruz faculty

press.ucsc.edu
Dimitris Achiloptas
Dimitris Achiloptas
Alexander Gamburd
Alexander Gamburd
Yi Zuo
Yi Zuo

The Alfred P. Sloan Foundation has selected three UCSC faculty members to receive 2007 Sloan Research Fellowships: Yi Zuo, assistant professor of molecular, cell, and developmental biology; Dimitris Achlioptas, assistant professor of computer science; and Alexander Gamburd, assistant professor of mathematics.
The Sloan awards are intended to enhance the careers of the very best young faculty members in specified fields of science. This year, a total of 116 fellowships were awarded in seven fields--chemistry, computational and evolutionary molecular biology, computer science, economics, mathematics, neuroscience, and physics. Each award includes a $45,000 grant that provides unrestricted support for research.
Zuo's research revolves around the communication between two classes of cells in the nervous system: neurons and glia. Despite the fact that glia constitute the majority of cells in the nervous system, their roles in neural circuitry have only begun to be understood. Zuo plans to use modern imaging techniques and molecular manipulation to study glia-neuron communication and understand how glia are involved in learning and memory. This research could suggest ways to manipulate brain function through modulating glial signals and lead to potential treatments for various neurodegenerative diseases.
Achlioptas's research in computer science addresses what are known as constraint satisfaction problems (CSPs). The popular number game Sudoku is a classic example of a CSP, where the variables are the contents of the empty squares, and the constraints arise from the rules of the game and contents of the filled-in squares. CSPs conceptually similar to Sudoku are found in many areas ranging from biology and biochemistry to software verification and airplane design, Achlioptas said. But while Sudoku problems can be solved in milliseconds by a computer using exhaustive search techniques, most real-life CSPs could not be solved that way. Achlioptas's work is aimed at designing algorithms for solving real-life CSPs using ideas inspired by statistical physics.
Gamburd's research in mathematics concerns spectral problems in number theory, probability, and combinatorics. He is particularly interested in problems related to random matrices and expander graphs.
One of the oldest fellowship programs in the country, the Sloan Research Fellowship Program began in 1955 as a means of encouraging research by young scholars at a critical time in their careers. The Alfred P. Sloan Foundation, a philanthropic nonprofit institution, was established in 1934 by Alfred P. Sloan Jr., the president and chief executive officer of the General Motors Corporation.

February 26, 2007
Contact: Tim Stephens (831) 459-2495; stephens@ucsc.edu
Sloan Research Fellowships awarded to three UC Santa Cruz faculty

February 27, 2007

Dundee mathematicians aid anti-cancer drug development

www.exduco.net
2007-02-23

The development of a new breed of "targeted" anti-cancer drugs is being boosted by mathematicians at the University of Dundee.
Dr Fordyce Davidson and Professor Mark Chaplain, both of the Division of Mathematics at the University of Dundee, have been awarded £160,000 to work with biotechnology company Cyclacel Pharmaceuticals, Inc. to develop the effective use of new anti-cancer drugs.
The grant from the Engineering and Physical Sciences Research Council will see the maths experts working alongside Cyclacel's Chief Scientific Officer, Dr Robert Jackson, and scientists at Cyclacel's Dundee, Scotland, laboratories on the company's new drug candidate, CYC116, one of a new breed of "targeted" anti-cancer drugs which are specifically designed to selectively kill cancer cells, leaving most other cells in the body unharmed.
One of the big challenges faced by doctors when treating cancer is to find out quickly whether a given treatment is effective or not for a particular patient. For certain cancers it can be very difficult to measure how quickly the tumour is shrinking in response to treatment - or indeed if it is shrinking at all. It can take several weeks before any change becomes apparent on a scan, for example. For particularly aggressive cancers, this delay can be lethal for the patient.
One possible way around this is to find other methods of measuring whether cancer cells are dying as a result of the treatment. The Maths Department at the University of Dundee has in recent years developed pioneering techniques in mathematical biology, using modelling to map the development of cancer tumours.
When cells are killed by anti-cancer drugs, tell-tale biochemical markers are released into the blood stream by the cell and it is possible that these 'biomarkers' could be used as a quick and accurate measure of the effectiveness of a drug. The test could be as simple as taking a blood sample.
However, as Dr Davidson explains, "The relationship between the amount of anti-cancer drug given to the patient, the effect that drug has on tumour cells and the subsequent concentration of biomarkers in the blood stream is very complex."
"Unfortunately it is not simply the case that higher quantities of a drug kill more cancer cells, it can be unpredictable. Moreover, all drugs can be harmful in large doses, so treatment has to be a clever balancing act."
"It is here that as mathematicians we will help by using powerful tools of mathematical modelling and analysis to understand the processes that take place once the drug is administered and how it can be most effectively applied."
The Dundee mathematicians, including new recruit Hitesh Mistry, will work closely with Cyclacel's scientists, to produce models of how the dose of Cyclacel's drug candidate, CYC116, an orally-available Aurora kinase and VEGFR2 inhibitor, impacts on tumour cell death and how this is reflected in the concentrations of biomarkers in the blood stream.
Dr Davidson said the advances being made in applying mathematical models to cancer diagnosis and treatment could help usher in a new era of personalised medicine.
"Ultimately this could lead to mathematical models in the form of computer packages being used by clinicians who would be able to key in information about a particular patient," he said.
"The model would then tell the clinician the most appropriate treatment regime and would also be able to help identify whether the chosen drug treatment was working. It is very exciting for us to be working with Cyclacel, developing this new technology alongside the new drug candidate".
Dr Robert Jackson, Cyclacel's Chief Scientific Officer commented, "The drug development process is becoming increasingly computer-intensive. The mathematical approaches being developed by Dundee University and those which we are using at Cyclacel together with our own biomarker analysis will help drug developers to interpret their biomarker data, and in the long term may increase drug development success rates and match patient treatments to their individual circumstances."
The project is being funded by the EPSRC via the `Mathematics for Business' scheme.
Dundee mathematicians aid anti-cancer drug development

February 27, 2007

First Woman to Receive ACM Turing Award

biz.yahoo.com
Tuesday February 20, 11:00 pm ET
IBM Fellow Emerita Frances Allen Responsible for Innovations to High Speed Computing; Work Inspired Generations of Computer Scientists

NEW YORK, Feb. 20 /PRNewswire/ -- ACM, the Association for Computing Machinery, has named Frances E. Allen the recipient of the 2006 A.M. Turing Award for contributions that fundamentally improved the performance of computer programs in solving problems, and accelerated the use of high performance computing. This award marks the first time that a woman has received this honor. The Turing Award, first presented in 1966, and named for British mathematician Alan M. Turing, is widely considered the "Nobel Prize in Computing." It carries a $100,000 prize, with financial support provided by Intel Corporation.
Allen, an IBM Fellow Emerita at the T.J. Watson Research Center, made fundamental contributions to the theory and practice of program optimization, which translates the users' problem-solving language statements into more efficient sequences of computer instructions. Her contributions also greatly extended earlier work in automatic program parallelization, which enables programs to use multiple processors simultaneously in order to obtain faster results. These techniques have made it possible to achieve high performance from computers while programming them in languages suitable to applications. They have contributed to advances in the use of high performance computers for solving problems such as weather forecasting, DNA matching, and national security functions.
"Fran Allen's work has led to remarkable advances in compiler design and machine architecture that are at the foundation of modern high-performance computing," said Ruzena Bajcsy, Chair of ACM's Turing Award Committee, and professor of Electrical and Engineering and Computer Science at the University of California, Berkeley. "Her contributions have spanned most of the history of computer science, and have made possible computing techniques that we rely on today in business and technology. It is interesting to note Allen's role in highly secret intelligence work on security codes for the organization now known as the National Security Agency, since it was Alan Turing, the namesake of this prestigious award, who devised techniques to help break the German codes during World War II," said Bajcsy, who is Emeritus Director of the Center for Information Technology Research in the Interest of Society (CITRIS) at Berkeley.
"Fran Allen's work on the Parallel TRANslation (PTRAN) project built on her earlier work on program optimization," said Andrew A. Chien, Intel's Vice President of Research. "Over the years, this foundation has enabled the advance of programming-productivity based on the co-evolution of higher level programming language and optimization technologies. It is particularly timely that this award comes as parallel computing is becoming an element of the most pervasive of computing platforms - laptop and desktop personal computers - and the opportunities for new and important contributions to parallel programming and efficient implementation abound," he said.
In 1989, Allen was the first woman to be named an IBM Fellow. In 2000, IBM created the Frances E. Allen Women in Technology Mentoring Award, naming her as its first recipient. As her Turing Award citation notes, she has been an inspirational mentor to younger researchers and a leader within the computing community. She is an Advisory Council Member of the Anita Borg Institute for Women and Technology, whose goal is to increase the participation of women in all aspects of technology. She also received the first Anita Borg Award for Technical Leadership, which was presented at Grace Hopper Celebration of Women in Computing in 2004.

Background

Allen joined IBM's T. J. Watson Research Center in 1957, to teach FORTRAN, a revolutionary high-level programming language, to the scientists at IBM. FORTRAN allowed scientists and engineers to write programs that closely resembled the mathematical formulas they normally relied on. Allen recognized the opportunity to address a grand challenge of high performance computers -- delivering the performance potential of computers to solve problems without exposing the underlying computer infrastructure.
Allen's 1966 paper, Program Optimization, laid the conceptual basis for systematic analysis and transformation of computer programs. Her 1970 papers, Control Flow Analysis and A Basis for Program Optimization established "intervals" as the context for efficient and effective data flow analysis and optimization. Much of her early work was done in collaboration with John Cocke, an IBM computer scientist who died in 2002. Her 1971 paper with John Cocke, A Catalog of Optimizing Transformations, provided the first description and systematization of optimizing transformations. She developed and implemented her methods as part of building compilers for the IBM STRETCH- HARVEST and the experimental Advanced Computing System. This work established the feasibility of modern machine- and language-independent optimizers.
In 1984, she formed and led IBM's PTRAN project to address the emerging challenge of parallel computers, which simultaneously executes related tasks for faster results. This project led to many advances including the concept of the program dependence graph, the primary structuring method used by most parallelizing compilers today.
In 1995, Allen was president of the IBM Academy of Technology, a global organization of IBM technical leaders charged with providing technical advice to the company. Before she retired in 2002, she was a Senior Technical Advisor to the Research Vice President for Solutions, Applications and Services. She is a member of the National Academy of Engineering, the American Academy of Arts and Sciences, and the American Philosophical Society. She was named a Fellow of ACM in 1994.
Allen has been a member of the Computer Science and Telecommunications Board (CSTB), the Computing Research Association (CRA) Board, and the National Science Foundation's Computer and Information Science and Engineering (CISE) Advisory Board. Her recent professional activities for ACM include membership on ACM's Job Migration Task Force, which produced the widely reported "Globalization and Offshoring of Software" study www.acm.org/globalizationreport/pdf/fullfinal.pdf. In addition, she was active in the ACM Special Interest Group on Programming Languages (SIGPLAN), and has served on the editorial boards of several ACM journals.
Among Allen's teaching and lecturing roles were visiting professor at New York University from 1970-73; consulting professor at Stanford University; the Chancellor's Distinguished Lecturer and Mackay Lecturer at the University of California, Berkeley in 1988-89; and Regents Lecturer at the University of California, San Diego in 1997. She was awarded Honorary Doctor of Science degrees from the University of Alberta in 1991; from Pace University in 1999; and from the University of Illinois, Urbana-Champaign in 2004. She graduated from Albany State Teachers College -- now the State University of New York at Albany -- with a degree in mathematics. She received a master's degree in mathematics at the University of Michigan.
ACM will present the Turing Award at the annual ACM Awards Banquet on June 9, 2007, in San Diego, CA.

About the ACM A.M. Turing Award
The ACM A.M. Turing Award was named for Alan M. Turing, the British mathematician who articulated the mathematical foundation and limits of computing, and who was a key contributor to the Allied cryptanalysis of the German Enigma cipher during World War II. Since its inception, the Turing Award has honored the computer scientists and engineers who created the systems and underlying theoretical foundations that have propelled the information technology industry. For additional information, click on http://www.acm.org/awards/taward.html.

About ACM
ACM, the Association for Computing Machinery http://www.acm.org, is an educational and scientific society uniting the world's computing educators, researchers and professionals to inspire dialogue, share resources and address the field's challenges. ACM strengthens the profession's collective voice through strong leadership, promotion of the highest standards, and recognition of technical excellence. ACM supports the professional growth of its members by providing opportunities for life-long learning, career development, and professional networking.
First Woman to Receive ACM Turing Award

February 27, 2007

New mathematical model developed for plastic packaging

www.foodproductiondaily.com
By Ahmed ElAmin
20/02/2007 - A new mathematical model developed by German researchers is designed to help processors estimate the amount of plastic packaging additives that may migrate into foods.

EU regulations currently set maximum limits on how much of a packaging additive can end up in foods, with the general principle that none should be in the product in the first place.
A European Commission proposal made last year would impose even tougher regulation on packaging chemicals migration. Companies can be forced to pay for costly recalls if their food products are found to be over the limits.
The new modelling system was developed by researchers at the Fraunhofer Institute for Process Engineering and Packaging IVV as a means of helping companies stay on the right side of the law.
They are working with nine packaging companies as part of a collaborative EU-funded project called FoodMigrosure. So far the results suggest that current means of calculating additive migration may be two low.
The scientists claim their method is cheaper and more accurate than existing methods of calculation. They estimate companies can save on testing costs by a factor of between a hundred and a thousand times compared to sending samples to a laboratory.
"The cost of computer-assisted testing is much lower than for a laboratory test, and the results are far more accurate," the scientists claimed.
To develop the model the Fraunhofer scientists took random food samples and subjected them to chemical tests in a laboratory.
The researchers based their mathematical model on investigations of genuine foods rather than food simulants. The analyses were performed by all ten of the companies involved in the project – resulting in what the scientists are saying is the world's only systematic collection of such data.
Normally, for such experiments testers replace the foodstuffs with legally prescribed food simulants such as olive oil and mixtures of water with acetic acid or alcohol.
"However, we have found that it is not usually possible to draw conclusions about solid foods on the basis of results obtained with liquid food simulants," said project coordinator Roland Franz. "In many cases the contamination of the foodstuffs is higher than hitherto assumed, and that necessitates costly product recalls."
Using their alternative method to test genuine foods, the scientists next developed various models on the basis of these data.
One model shows how the additives move about in the plastic. Another shows how many of the substances migrate from the plastic packaging material into a particular food.
A third model describes how the migrants disperse in the food itself, Franz said. The researchers devised a formula to summarise the models.
The formula takes into account such characteristics as structure, fat content and consistency and weds the data to the type of plastic packaging material used. The model also takes into account the various additives and the average quantity of the foodstuff actually eaten by consumers.
The same formula can thus be used on one occasion to calculate how many packaging additives are present in cheese, and on another occasion to do the same for meat or orange juice.
Last year the European Commission proposed legislation that would define the manufacturing practices the bloc's processors would have to take in ensuring that packaging materials do not migrate into foods.
All companies would be required to follow what the law defines as "good manufacturing practice" (GMP) in ensuring that packaging chemicals do not transfer to the foods.
GMP would require food companies to change their production methods to prevent the possibility of packaging substances transferring to foods. The proposed requirements would apply to chemicals that might not give rise to particular health concerns but which should not be in foods. They also apply to active and intelligent materials used in packaging to extend shelf life or indicate when food is off.
The proposals are partially an outcome of food safety crisis in November 2005 in which Italy's regulators discovered that a printing chemical from a Tetra Pak package was found to have migrated into a Nestlé milk product for babies.
The EU last year opened a commmunity reference lab in Italy designed aas joint research centre into the safety of specific packaging chemicals, such as those used in inks or for making the material.
EU legislation requires that all materials that come into contact with food comply with health standards so that safe food remains safe.
The new EU reference laboratory will set standards for testing practices for food contact materials across the EU.
It will also serve as a point of reference for issues relating to the enforcement of legislation on food contact materials.
This will be achieved through a network of national reference laboratories set up by each member country.
It will develop methods, reference substances, and training procedures to ensure consistent testing practices are done nationally to ensure the best possible implementation of EU legislation, said the science and research commissioner, Janez Potoènik.
New mathematical model developed for plastic packaging

February 19, 2007

IT'S ALL IN THE MIND

www.telegraphindia.com
John Nash
Few winners of the Nobel Prize for economics are household names. But the film A Beautiful Mind made John Nash a celebrity — even in India, as he is discovering.

John Forbes Nash is a reluctant celebrity. The arclights are on him and he looks old and weary in the glare. Just this month, at least three Nobel laureates have visited India. Two of the three — all equally accomplished and distinguished in global academic circles — have landed and left without much ado or fanfare. But Nash is the chosen darling of the media.
The ensuing circus, however, has little to do with his pioneering work in mathematics and game theory. The point of interest is the award-winning film A Beautiful Mind, starring Russell Crowe. It was the film that shot Nash out of academic circles and into dinner table conversations, making him a household name.
But Nash sits slouched in a plush armchair in the Maurya Sheraton in south Delhi, visibly exhausted and besieged by reporters. "This has been like a business trip," he says quietly, burrowing deeper into the armchair.
Nash is in India for a week on the invitation of the ministry of external affairs to flag off its new Nobel Laureate Lecture series. Within three days of being in Delhi, he has delivered a public lecture and met the Prime Minister and the President. He was in Bangalore on Friday to meet Infosys chief mentor Narayana Murthy, and then in Mumbai for a lecture on "Ideal Money and Asymptotically Ideal Money."
Worn out after a day trip to Delhi's landmarks and a constant salvo of questions and meetings, 79-year-old Nash just sits silently, surrounded by his wife, Alicia and his son, John Martin. It's a surreal picture — Nash carries a humungous calculator, and John, a book called Windows for Dummies.
But surreal, really, is better used to describe Nash's roller-coaster ride of a life. A PhD holder at 22, he went on to solve many of the seemingly impenetrable mathematical challenges of the time. His interest in mathematics was kindled when he was a young boy and read the book Men of Mathematics by E.T. Bell. But it was his slender 27-page doctoral thesis, "Non-cooperative Games", as a Princeton student on game theory that won him the Nobel Prize for economic sciences in 1994.
"Nash's work on game theory is the central nerve of the field. I use the Nash Equilibrium in half of my work," says US-based Pradeep Dubey, game theorist and a personal friend of Nash. Nash established the mathematical principles of game theory, which offers to explain the complicated process through which governments, corporations and individuals reach strategic options. Game theory can be applied to almost anything, from a conflict situation to international negotiations to marriages. A lesser known fact about Nash is that he co-invented two famous games, Hex and So Long Sucker, which are still played across campuses.
But as young Nash stood at the edge of what was expected to be an extraordinary career dotted with achievements, fate had other designs. The debilitating illness of paranoid schizophrenia and irrational voices in his head gradually drove Nash out of academic elite circles and frequently banished him into involuntary confinements in hospitals. But even during the so-called irrational period of his life, Nash published numerous papers which have inspired subsequent work as well.
But the brief periods of remission were like coming up for air, as he kept slipping back every time. It took him nearly 25 years to finally shake off the illness. During these years, Nash came to be known as the "Phantom of the Fine Hall" in Princeton, where he wandered about silently, doodling arcane equations on blackboards. Nash was slowly able to defeat the disease without hospitals or medication.
Apart from his innate genius, Nash's stalwart has been Alicia, his wife, friend and loyal companion. Married in 1957, Alicia was pregnant with their first child when Nash started to decline into a delusional abyss. By 1963, Alicia and Nash were divorced, though she did take him back as a lodger in 1970. Alicia's faith and patience were instrumental in Nash's re-emergence as a normal mathematician.
He was back to normal life in Princeton by the time the Nobel was announced. "He asked me to stay at home and listen to the phone. Finally I think I answered it and we were both…," said Alicia throwing up her hands.
Alicia re-married Nash in 2001, after 38 years. Her life has been dedicated to Nash, through illness and recovery, and to their son. Unfortunately, Martin has also been diagnosed with schizophrenia and has suffered nervous breakdowns. "It is like déjà vu. But an illness is an illness. Knowing about it or living it twice doesn't cure it," says Alicia.
Nash is a deeply private person. He refused to dole out personal details either for the highly acclaimed biography A Beautiful Mind by Sylvia Nasar, or the motion picture. "He once told me that he was relieved to see the movie because he didn't feel that his privacy was invaded. It's a take-off on his life. The film showed Nash breaking a lot of codes for the US government but I don't think he did that," says Dubey.
And to answer the oft-asked question, Nash does not look anything like the pumped-up Crowe in the film. But Martin uncannily resembles Crowe, towering over everyone in a baseball cap.
Nash's life is scripted almost along cinematic lines, as if it were always meant to be one. From early childhood, through the prolific years of his youth, tortured delusions and then back to a normal life, mathematics has always stood by him. Ironically, his greatest award in 1994 was not for his work in pure mathematics but for economics. And that too for his work in the 1950s. "Nash should have received the Nobel years back. To give it so late makes the Nobel prize slightly less noble," says Dubey.
For all his personal and academic milestones, people close to Nash say he is grounded and considerate — an individual without airs. "He is very real. He is like a little boy," says actress Lushin Dubey, a friend to both Alicia and Nash. And just as the three of them walk away to another busy evening, Nash turns back slowly to add, "I would have liked to see more of the Indian countryside. Maybe another time." Just like he said in 1950, for a perfect solution, you win some, you lose some.
IT'S ALL IN THE MIND

February 19, 2007

There are many people out there who have more fame than me: Nash

www.dnaindia.com
Monday, February 19, 2007 01:25 IST

American mathematician and economist John Nash will be arriving in Mumbai on Monday to deliver a lecture on the economics of money and, in his words, "to explore the new, emerging India for himself." Nash, famously portrayed in the Oscar-winning movie A Beautiful Mind by Russell Crowe, won the Nobel Prize for economics in 1994. Josy Joseph spoke to the 79-year-old mathematician ahead of his Mumbai sojourn.

Having been a mathematical prodigy very early in life, what advice would you give children on learning to love numbers?
When I was young, I was sort of generally scientifically interested rather than specifically mathematics. I like to accumulate scientific knowledge. I could work with mathematics to do calculations — I had that interest. What is possible to do is simply to develop the ability to work with larger numbers.
How important is mathematics to an aspiring economist? Do the two go hand in hand?
It helps to have a good foundation in mathematics, to study mathematical economics. I can't say exactly how much one should study; there are a lot of variations. Counting and measuring is something age old. The Babylonians learnt how to keep accounts. That is sort of right at the beginning on a world basis, except for western hemisphere.
They also developed independently.
A genius is a difficult state of mind and being. You are being asked to comment on everything from globalisation to Hollywood. How do you handle all that?
I don't accept the genius concept, this is a word many people use. I don't say they shouldn't use it either. I haven't ever tried an IQ test. It is something meant for children, they need to develop. People generally ask questions. I am effectively fame-less. There are many people out there who have more fame than me in many ways, than I do. They may not be so broad but they have distinguished reputation.
How has been life after the movie, A Beautiful Mind? Has the movie made much impact on your life?
The movie has been out for a while now. It was made in 2002, so that is now five years ago. There has been a quite a change in the reaction I got — a lot more fan mail for one.
Do other factors, gadgets like mobile phone contribute to distractions?
The mobile phone is a very interesting example. A great technological advancement. I think time would come when we all ought to have it. I am avoiding it, I say I don't want to be distracted. It saves money. For an older person it might be a life-saver.
I think there will come a time when you really ought to have one, fitted into your car. So if you have a breakdown in your car, or such situations, it would be a life-saver. I don?t know if it is affordable. I don't use a portable computer also. But I have a computer (PC) at home, also one at office, which are pretty old. Notebooks are pretty recent.
How are the principles of game theory being applied in today's political scenario?
In the US there was a considerable effort to apply game theory during the Cold War period. A more recently case for analysis is the situation in Iraq, when it was reported that the US lost five helicopters and its crew in a short period of time because people were using smaller missiles to shoot them down. The American side said the shock- and-awe tactics would do the work. But then the US army began using helicopters like buses to transport soldiers from one point to another.
As a mathematician and economist how do you look at the future of globalisation?
There is a general lesson in economics and finance that it is always learnt and then forgotten — you have to expect surprises, things will not just continue smoothly.
There will be surprises.

John Nash unplugged
John Forbes Nash, Jr. was born on June 13, 1928 in Bluefield, West Virginia. He studied engineering and chemistry at the Carnegie Mellon University before switching to mathematics.
In 1978, Nash was awarded the John Von Neumann Theory Prize for his invention of non-cooperative equilibria, now called Nash equilibria. He won the Leroy P Steele Prize in 1999.
He shared the 1994 Nobel Prize in Economics with two other game theorists, Reinhard Selten and John Harsanyi.
Nash is known in popular culture as the subject of the Hollywood movie, A Beautiful Mind, about his mathematical genius and his struggles with schizophrenia.
There are many people out there who have more fame than me: Nash

February 19, 2007

The mind battles on

www.hindustantimes.com
Aditya Sinha
New Delhi, February 17, 2007

My 40 minutes with Nobel Laureate John Forbes Nash Jr was a little strange. The 79-year-old mathematician who won the 1994 prize for economics said he was suffering jet lag and a packed schedule, but there was something else.
The external affairs ministry, which organised the interview, had said there should be no questions about paranoid schizophrenia, the illness he was diagnosed with when he was 30, and for which he spent six involuntary hospitalisations. His biography, A Beautiful Mind, made into a film, says he spent the next 30 years coming to terms with it, and that his story was one of "genius, madness, reawakening". And so I thought it was something in the past.
During the chat, Nash appeared a man who was cautious. His answers were uneven, and at time, inexplicable. And on two occasions our eyes met — for the most part he kept diverting his gaze — I saw an unsettling fear and sadness. Yet when a maths-related question was posed, he seemed to change into a different person: lucid and brilliant. I did not give it much thought at the time. But later, I woke up in the middle of the night, with the realisation that perhaps I witnessed a battle between genius and madness within an individual.
Not exactly, practicising psycho-analyst Madhu Sarin says: "High IQs have been linked to greater sensitivity; brilliance and battiness have gone hand-in-hand." Nimesh G. Desai, head of psychiatry at the Institute of Human Behaviour and Allied Sciences, says the rate of disorders is high at the extremes of intelligence. "The hallmark of creativity is original thought," Desai says. "Original thoughts often fall within the realm of abnormal. This abnormal idea may be something that can make a critical difference to humanity, or it may stem from a psychiatric disorder. The boundary between the two may be blurred."
Schizophrenics lose a sense of continuity, says Sarin, so they lose a sense of self. In turn, this means they lose sight of the other person as well. So during the conversation, what was happening was that Nash was responding to however I gestured — but on a moment-to-moment basis. The only constant for him, perhaps, was a literal feeling of coming apart, Sarin says, which projected onto me as an eerie feeling.
"The kind of anxiety schizophrenics feel you can't begin to imagine," Sarin says. And to deal with uncertainty, schizophrenics take refuge in a rational universe — like mathematics — where their feelings are neatly packaged. True enough, Nash spoke about 9/11. Unlike most other Americans, he spoke of it calmly, as an incident perpetrated by insane people, directing his criticism at his government's reaction to the incident. As he could not handle an intensity of emotion, he took his analysis to a logical extreme.
So my earlier notion, that his battle against schizophrenia had been long won, was wrong. "It's never over, you can only improve the quality of life," says Sarin. For 40 minutes, I had a glimpse of his beautiful mind's fight against a dissipating self, and saw that indeed, beauty is fragile.

(With Neha Mehta)
The mind battles on

February 19, 2007

Alum Creates Math Encyclopedia on Web

www.cornellsun.com
By Lisa Grossman
Sun Staff Writer
Feb 19 2007

A classroom in Rhodes Hall was packed on Friday afternoon when mathematicians, physicists, engineers and other fans of the MathWorld website gathered to hear its creator, Eric Weisstein '90, give a talk entitled "MathWorld: Communicating Mathematics on the Internet" as part of the Center for Applied Mathematics Colloquium series.
MathWorld is a free online encyclopedia of mathematical terms, concepts and definitions. To date, it has over 12,600 pages, and is updated continually to reflect new discoveries and information. Many Cornellians, students and faculty alike consider the site an invaluable resource. What most don't realize is that Weisstein wrote nearly every page entirely by himself.
MathWorld's initial form was created in 1987 when Weisstein was an undergraduate physics major at Cornell. Possessed with an admirable work ethic, Weisstein typed up all of his physics and math lecture notes in Microsoft Word.
"The reason [MathWorld] exists is because it didn't exist when I was a student, and I really, really wanted it to," Weisstein said. "This is made for you."
By 1991, he had amassed 82 pages of detailed, neatly typed math notes, saved as a Word document on his computer. When the first version of Netscape came out in 1994, he decided to convert his notes into a web page, titled "Eric's Treasure Trove of Mathematics."
"I wanted to spread the gospel of mathematics," he said. "I had hoped to do so through my research papers, but I realized that the number of people who were seeing my website was about an order of magnitude higher than the number of people who read my papers."
After a legal dispute, the site went back up in 2001, and has been growing steadily ever since. Today, if it were published as a book, MathWorld would be about 4,300 pages long. The site gets hundreds of thousands of page hits every day from all over the world. Google search results rank it as the number one math and science website. According to Weisstein, most people who find their way to MathWorld do so through Google: if you Google an obscure mathematical fact, MathWorld will nearly always come up as one of the top hits.
Weisstein mentioned that there are a number of other ways to navigate the MathWorld site as well, including its own internal search engine and the "Random Entry" link. Weisstein once got an e-mail from a user who relied extensively on the "Random Entry" link as a research tool.
"One time he was trying to remember a concept from linear algebra, and he couldn't remember its name, but he knew someone must have written about it at some point. So he hit 'Random Entry' 800 times to see if it would come up. And he found it!" Weisstein said. "If you make the tools, people will use them."
To Weisstein, the most important function that MathWorld serves is reaching as wide and diverse an audience as possible.
"MathWorld disseminates math knowledge to people worldwide — to teachers, students, farmers in Africa..." Weisstein said. "It shows potential scientists and mathematicians that math is fun and interesting and it's something they can do — it's not something they should be scared of. That's the important thing," he said. While thousands of users have contributed comments and corrections to MathWorld, 99 percent of it was authored exclusively by Weisstein. When asked if he would ever consider hiring people to help him write, Weisstein was reluctant.
"This was a labor of love for me," he said. "I love writing about it, and I think I have a different approach than a lot of textbooks I've read."
Keeping the style and the level of accessibility consistent is more important to him than being able to publish more quickly and efficiently.
Catherine Elder '08, who attended the talk, prefers MathWorld to Wikipedia.
"When I was working on a physics problem set and I couldn't remember something that I learned in high school, I used to Google it," she said. "A lot of the time, MathWorld or Wikipedia would come up. Recently, I noticed that the Wikipedia articles often cite MathWorld. Now, I just go straight to MathWorld."
Throughout his talk, Weisstein was funny, entertaining and personable.
"It was nice to put a personality to the website," Elder said. "It seemed like we could relate to each other a lot."
A number of students and professors approached Weisstein after the talk to thank him, including one of Weisstein's former professors, David Chernoff, astronomy. "I thought his talk was wonderful," Chernoff said. "He has a creative and independent spirit with a strong personal interest in learning and explicating the math and science he covers on his web site. ...His approach makes it possible to gain a broad understanding of mathematical terms and ideas with a minimum of effort. It's been extremely helpful to those of us who aren't experts but want a better sense of the meanings and connections of various terms."

By Lisa Grossman at Feb 19 2007 - 1:43am
Alum Creates Math Encyclopedia on Web

February 19, 2007

Mathematical Model Predicts Cholera Outbreaks

www.sciencedaily.com
Science Daily — A mathematical model of disease cycles developed at the University of Michigan shows promise for predicting cholera outbreaks.

Speaking in a symposium titled "New Vistas in the Mathematics of Ecology and Evolution" at the annual meeting of the American Association for the Advancement of Science in San Francisco, theoretical ecologist Mercedes Pascual will discuss how models that she and coworkers have developed can aid short-term forecasting of infectious diseases, such as cholera, and inform decisions about vaccination and other disease-prevention strategies.
In research done over the past seven years, Pascual and colleagues have found evidence that a phenomenon known as the El Nino-Southern Oscillation (ENSO), a major source of climate variability from year to year, influences cycles of cholera in Bangladesh. They also showed that the coupling between climate variability and cholera cycles has become stronger in recent decades.
Now, Pascual is examining the feasibility of using a model developed during that work as an early warning system.
"The question we asked was whether, using data from 1966 to 2000, we could have predicted cholera outbreaks over the past five years," said Pascual, an associate professor of ecology and evolutionary biology. "We also wanted to know whether incorporating ENSO into the model would improve the accuracy of our predictions." The challenge for the model was particularly interesting because the past five years were atypical, with fewer cholera cases than usual and no strong climate anomalies. However, the model performed well, Pascual said.
"Our results showed that for the past five years, we would have done fairly well predicting cholera cases one year ahead, and that the model that uses ENSO makes prediction even more accurate."
Cholera, a serious health problem in many parts of the world, results from a bacterial infection. The bacterium takes up residence in the intestines, causing vomiting and diarrhea, which can lead to severe dehydration and death if patients are not promptly treated.

Note: This story has been adapted from a news release issued by University of Michigan.
Mathematical Model Predicts Cholera Outbreaks

February 19, 2007

Graph Theory and Teatime

www.sciam.com
Deep in the heart of Microsoft, Jennifer Chayes and Christian Borgs lead a who's who of mathematics and computer science.
The goal? To explore anything they please

By Gary Stix
CHRISTIAN BORGS AND JENNIFER CHAYES
CHRISTIAN BORGS AND JENNIFER CHAYES:
THEORIZING AT MICROSOFT

Every weekday afternoon some 20 mathematicians and theoretical computer scientists gather in the Seattle suburbs to share tea. The conversation runs from the latest on number theory to the fairest way to decide a closely contested election. The gathering spot is not the faculty lounge of an elite university but rather a meeting area in Building 113, the nondescript glass and steel structure that houses the Theory Group of Microsoft Research.
A decade ago two mathematical physicists--Jennifer Chayes and Christian Borgs--gave up permanent academic positions for the allure of being able to go out and hire the best minds in discrete mathematics, statistical physics and theoretical computer science. By most measures, the pair have succeeded in re-creating the rarefied world of a top university department, right down to the tea ritual. In essence, the group resembles a smaller version of the Mathematical Sciences Research Center in its heyday at the old Bell Labs, home to Claude E. Shannon, Richard Hamming, Narendra Karmarkar and other quantitative luminaries, before corporate upheavals ultimately forced a scaling back. "It would be very hard, if not just impossible, for a university to assemble such a group within a 10-year time frame," remarks Bart Selman, professor of computer science at Cornell University and also a former Bell Labs researcher. "Clearly, Microsoft resources play a role here."
Microsoft Research was established in 1991 to emphasize basic research in computer science at a time when other industrial labs were revamping to focus on more applied endeavors. The Theory Group, whose members routinely publish papers with titles such as "The D4 Root System Is Not Universally Optimal," probably has the least relevance to product development of any Microsoft department.
The disconnect is intentional. In 1996 Nathan Myhrv­old, a former classmate of Chayes at Princeton University who was then Microsoft's chief technology officer, suggested that Chayes and Borgs come to work at Microsoft. "Are you crazy?" Chayes asked Myhr­vold. "You can't make money from what we do."
Myhrvold promised that they would not be enlisted to write code for a new version of Microsoft Office. "He wanted us to do the most way-out stuff," Chayes remembers. "He said, 'Look, I'm not hiring two engineers,'" Borgs chimes in a moment later. The Microsoft offer solved a fundamental problem related to time and space. The two had married four years earlier. Chayes was a tenured professor of mathematics at the University of California, Los Angeles. Borgs had a chaired professorship in statistical physics at the University of Leipzig in Germany.
"We went from living on the other side of the world to doing everything together," Chayes says. Every paper they write bears joint authorship; every intern candidate interviewed receives questions from both. The compatible trajectories stretch back to their youth. Neither followed the rectilinear path set out for them by their parents. Borgs, 49, came from a traditional family in Düsseldorf, Germany, and was expected to take over their 120-year-old chemical business. Chayes, 50, a rebellious "child of the sixties" and the daughter of a Jewish father and a Muslim mother who had immigrated to the U.S. from Iran, was supposed to become a physician. (Her brother, James Tour, also paid no heed to his parents' plans, going on to become a chemist at Rice University and a major figure in nanotechnology.) The collaborating spouses held Myhrvold to his word and went on to hire some of the best and brightest. There are nine full-time researchers, eight postdoctoral students, five academics on sabbatical from other institutions--and 150 to 200 visitors annually who arrive for stays that range from a day to a month. "Their list of visitors reads like a veritable who's who of theoretical computer science," observes Lenore Blum, a computer scientist at Carnegie Mellon University.
The quasi-academic environment has enabled notable researchers to continue their work undistracted--or, if they so choose, to branch out in new directions. Oded Schramm devised a mathematical proof that shows how certain random two-dimensional objects, when distorted, retain the same statistical properties--a characteristic called conformal invariance. One of Schramm's colleagues, Wendelin Werner, received the Fields Medal for this work. (Schramm was a few weeks too old to qualify for the medal, bestowed only on those younger than 40.) "Oded basically invented a new branch of mathematics, which I predict will be studied 100 years from now," Chayes says.
Another notable was Michael Freedman, who won the Fields Medal while at the University of California, San Diego, for his work on the Poincaré conjecture. He moved to the Theory Group in 1997 and began to explore in earnest how topological quantum field theory could be applied to create a quantum computer with very low error rates, taking advantage of the fact that topological properties resist perturbations (errors). Freedman has since formed his own group within Microsoft that focuses on quantum computation.
A younger researcher at 32, Henry Cohn has, along with postdoc Abhinav Kumar, published seminal work on how densely spheres can be packed together within eight and 24 dimensions. Mathematicians are fascinated by what Cohn calls these "miracle dimensions" because of packing efficiencies generally not found elsewhere. Such calculations may ultimately enable better error-correction codes for transmitting digital bits on noisy channels.
Chayes and Borgs have also been able to build on their original university work on the mathematics of phase transitions: sudden discontinuities in a physical state, such as when water turns to ice. Similarly, whenever increasing loads are placed on two parallel microprocessors, a phase transition occurs in which balancing work among the processing elements becomes much more difficult. In their papers, Chayes and Borgs have shown that once the transition has occurred, it may be virtually impossible to improve on a near-optimal solution to partitioning a workload--the programmer of a parallel processor cannot just shift some of the load from one processor to another to achieve the best balance. "You may as well start over," Chayes says. "That's a disaster for computation."
Besides computer science, this type of optimization problem has implications for modeling the precise networks of chemical bonds, genes and synapses that are found in investigations of protein folding, gene activation in microarray chips, and the changes in neural connections that occur during learning. Chayes and Borgs have undertaken a collaborative initiative with Riccardo Zecchina of the International Center for Theoretical Physics in Trieste, Italy, and other European researchers to explore a technique, called survey propagation, that might find better solutions for the hard optimization problems found after a phase transition occurs.
Chayes and Borgs's prior university labors on graph theory and phase transitions have been of some use to the enterprise. Since they joined Microsoft, the World Wide Web has come into its own. "All of a sudden the stuff we were doing has become relevant," Chayes notes. Graph theory serves as a powerful tool for modeling the complexity of the Web. Chayes and Borgs have shown how the patterns formed by links fanning out from spam sites differ in appearance from connections to normal sites, a tool that is being incorporated into search engines by Microsoft product developers.
For the pair, the fusion of work and personal life has proved essential for building both the Theory Group and continuing their own research. Certainly Borgs understands Chayes when she gets angry at her husband and shouts, "You're perturbing around the wrong ground state." The couple's overlapping orbitals have been good for their own careers, for Microsoft and for the larger community of mathematicians and computer scientists.
Graph Theory and Teatime
February 19, 2007

Patterns Patterns Everywhere

www.aapress.com
Martin Golubitsky
Professor Martin Golubitsky

Martin Golubitsky, Cullen Distinguished Professor of Mathematics at the University of Houston, will deliver a lecture aimed at the general public entitled "Patterns Patterns Everywhere" on March 7, 2007 at 7:00 p.m. in Room 125 of Willey Hall, 225 19th Avenue S., Minneapolis, MN 55455 on the west bank campus of the University of Minnesota.
Regular patterns appear all around us: from vast geological formations to the ripples in a vibrating coffee cup, from the gaits of trotting horses to tongues of flames, and even in visual hallucinations. The mathematical notion of symmetry is a key to understanding how and why these patterns form. In this lecture Professor Golubitsky will show some of these fascinating patterns and explain how mathematical symmetry enters the picture.
Learn more about Professor Golubitsky online at www.math.uh.edu/~mg.
The lecture is part of the series "Math Matters" sponsored by the Institute for Mathematics and its Applications. The event free and open to the public. For more information visit online at www.ima.umn.edu, email: scheelaima.umn.edu, or call 612-624-6066.

Posted on 15 Feb 2007 by Tlaventure
Patterns Patterns Everywhere

February 19, 2007

Birthday finds Hauptman embarking on new research

www.buffalonews.com
Herbert A. Hauptman
Charles Lewis/Buffalo News
Nobel laureate Herbert A. Hauptman,
shown examining one of his dodecahedrons,
will celebrate his 90th birthday today
with a party at the research institute bearing his name.

By TOM BUCKHAM News Staff Reporter 2/14/2007
Nobel laureate Herbert A. Hauptman, who turns 90 today, says he is slowing down. Just a bit, mind you.
"I have to admit I no longer have the energy I did when I was only 80," he quipped. "I can't work as hard as I used to. In the old days, I did my best work after midnight; I can't do that now."
Nor is Hauptman, who will be toasted this evening during a birthday party in the Hauptman-Woodward Medical Research Institute, "as steady on my feet" as before. He is pondering whether to hire a driver for the daily trip from his Amherst home to the institute's glittering new downtown building. "It makes sense, but I probably won't," he said.
Of course, none of this means Hauptman, who shared the 1985 Nobel Prize in chemistry with Jerome Karle, a former colleague at the Naval Research Laboratory in Washington, D.C., intends to scale back his research activity.
In fact, he and scientists in France and Japan recently received a $1 million grant from the International Human Frontier Science Program Organization to develop a method called neutron diffraction for crystallography research.
"It gives me a job for another three years," shrugged Hauptman, who is president of Hauptman-Woodward, a world leader in the field. Crystallographers spend their time searching for the structure of proteins - discoveries that might lead to new drugs for AIDS, Alzheimer's disease, cancer, heart disease and other illnesses.
"At my age, I wasn't seriously thinking of making another proposal," Hauptman said. But he reconsidered. The joint request for neutron diffraction funding, based on a paper he wrote three years ago, ranked first among 20 proposals accepted by the international organization, out of 1,000 submitted by scientists around the globe.
Until now, X-rays have been the basic research tool in crystallography. "What we did not expect was that bombing atoms with neutrons would be better than X-rays," said Hauptman, who will serve as principal investigator on the international research project. "It doubles the amount of experimental data we get."
Hauptman-Woodward "has the ability to grow proteins, and we're strong in mathematics," he said. "France has biocehmistry and biology, and Japan has the ability to do the experiments."
Though his legacy is secure, Hauptman worries that young researchers following in his footsteps may be unable to attract funding for their work. Established scientists always can find sponsors, but those who haven't made a name for themselves, including several recruited by Hauptman-Woodward for its state-of-the-art laboratory, must rely primarily on grants from the National Institutes of Health and National Science Foundation.
Because of the "billions and billions" being funneled into the Iraq War, federal research money is drying up fast, Hauptman said. "I'm very afraid that our younger guys, who show so much promise, will not be funded."
Looking back, Hauptman said moving to Buffalo in 1970 was vital to his career, although his wife, Edith, had strong misgivings at the time.
After more than two decades at the Naval Research Lab, where he applied mathematical formulas to the quest for submicroscopic proteins, "they found out that what I was doing had nothing to do with the Navy mission and tried to steer me away from it," he said.
The Medical Foundation of Buffalo, later renamed Hauptman-Woodward, was a much better fit. Teaming up with scientists who included William Duax, Vivian Cody and Chuck Weeks "worked out beautifully," he said. "They complemented my work, which was exclusively theoretical, in a perfect way."
"If I hadn't been able to continue my work here, the Nobel Prize might not have come," he added.

For the record, the marriage survived. He and Edith have been married 66 years and still get up at 6:30 a.m. several times a week to swim. They have two daughters, Barbara and Carol. The birthday celebration will feature the unveiling of Hauptman's Nobel medal and mathematical stained-glass sculptures - dodecahedrons packed with spheres of four different sizes. He donated the collections for a permanent exhibit in the Hauptman-Woodward lobby.
Birthday finds Hauptman embarking on new research
February 19, 2007

Computer Tool Helps Pinpoint Risky Gene Mutations;
Mathematical Analysis Could Aid in Predicting Cancer Cases

newswire.ascribe.org
BALTIMORE, Feb. 15 (AScribe Newswire) -- Certain cancer risks can be passed down through families, the result of tiny changes in a family's genetic code. But not all genetic changes are deadly. To help medical counselors and physicians identify the mutations that pose the greatest health risks, researchers at four institutions, including Johns Hopkins, have developed and validated a new computer tool.
The system, described in the Feb. 16 issue of Public Library of Science Computational Biology, evaluates 16 "predictive features" to help answer a critical question: Is a particular mutation a harmless variation or a genetic glitch that could set the stage for cancer? In blind biochemical tests involving 36 samples containing genetic mutations whose association with breast and ovarian cancer was unknown, the computer tool demonstrated an accuracy rate exceeding 94 percent in identifying protein functions that are believed to be linked to a higher risk of cancer.
The researchers cautioned that the computer tool by itself cannot yet predict future cancer cases. But they believe it can be a fast and useful supplement to traditional biochemical tests, which are far more time-consuming, costly and labor-intensive, and do not always yield conclusive results.
"When people are diagnosed with certain types of cancer, other family members sometimes get genetic testing to find out if they, too, are predisposed to this disease," said Rachel Karchin, an assistant professor of biomedical engineering at Johns Hopkins and lead author of the journal article. "But sometimes, the standard tests find small genetic variations that may be harmful or benign. Our computational test may help pinpoint which one it is. We hope the system will eventually give counselors and doctors an important new tool to help them advise patients about whether they need to take preventive steps to keep cancer from developing."
Karchin, who earned a doctorate in computer science from the University of California, Santa Cruz, joined Johns Hopkins last September as a participant in the university's Institute for Computational Medicine. "There are some things you can do with a computer that we hope will be useful in predicting the cancer risks associated with some genetic mutations," she said. "We're not quite there yet, but that's our goal."
Karchin began working on the new computer tool as a postdoctoral fellow in the lab of Andrej Sali, a professor of biopharmaceutical sciences and pharmaceutical chemistry at the University of California, San Francisco. For the current journal article, the biochemical tests to validate the computer tool were conducted in the lab of Alvaro Monteiro at the H. Lee Moffitt Cancer Center & Research Institute in Tampa, Fla. Sali and Monteiro are co-authors of the journal article.
In their experiments, the researchers focused on inherited mutations in the BRCA1 gene. A significant number of breast and ovarian cancer cases are believed to be caused by such mutations, possibly because they disable a gene that normally suppresses cancer.
To test the computer tool, Karchin and her colleagues used it to analyze 36 "point mutants" on the BRCA1 gene, meaning locations where a single letter in a string of DNA differed from the sequence found in the general population. This mutation caused an amino acid residue change in the protein produced by the gene. "Some of these types of variations can put a woman at greater risk for developing ovarian or breast cancer," Karchin said. "The question is: Which ones?"
To answer it, the researchers examined 16 factors in three categories. One category focused on whether the mutated genes produced proteins that performed their jobs properly. The second involved studies of the physical structure of the mutated gene. The third category was an assessment of the gene's evolutionary history, looking at how long the changed amino acid residue position has been preserved in various organisms. The last category is important because harmful mutations tend to be eliminated by evolutionary selection because of the damage they inflict on their carriers.
The researchers plugged these factors into a computer formula that identified the gene mutations most likely to be linked with cancer. Karchin was pleased that the system was highly successful at finding harmful mutations during the blind tests in Monteiro's lab. She believes it has a promising future. "Genetic counselors now base some of their advice on family history," she said. "But family histories are often incomplete. If we can give genetic counselors another tool, it could be very helpful to a lot of people."
The other co-authors of the journal paper were Sean V. Tavtigian of the International Agency for Research on Cancer in Lyon, France, and Marcelo A. Carvalho of the Moffitt Cancer Center. The research was supported by grants from the National Institutes of Health.
Digital color photo of Rachel Karchin available; contact Phil Sneiderman.

Related Links:
Rachel Karchin's Lab Page: http://karchinlab.org/
Institute for Computational Medicine at Johns Hopkins: http://www.icm.jhu.edu/
Johns Hopkins Department of Biomedical Engineering: http://www.bme.jhu.edu

MEDIA CONTACT: Phil Sneiderman, JHU Media Relations, 443-287-9960, prs@jhu.edu
Computer Tool Helps Pinpoint Risky Gene Mutations; Mathematical Analysis Could Aid in Predicting Cancer Cases

February 19, 2007

A quantum logic

www.onlineopinion.com.au
Peter and Rupert pass in the hallway of an Australian ICT research organisation. Peter, a research scientist utters to Rupert, the business development manager, "How is it going with John?" This utterance is the tip of an ice-berg rich in implicit associations. Due to their shared context, Peter and Rupert both know that "John" refers to "John Smith" of "ACME Corp", who is negotiating a commercial license for "Guidebeam", a next generation web-based search technology.
In the not so distant future our information environment will feature all sorts of devices and displays. Imagine the existence of a technology looming in the background which processes the above utterance, draws appropriate context sensitive associations in order to flesh it out, and thereafter uses the result to query for emails, license documents, podcasts of relevant conversations and so on, and tacitly retrieves these to prime Rupert and Peter's immediate information environment.
For example, the licence document and associated emails could be brought up on the wall display should they be needed for further reference in Peter and Rupert's spontaneous hallway discussion.
The above scenario illustrates that human beings are adept at drawing context-sensitive associations and inferences across a broad range of situations ranging from the mundane to the creative inferences that lead to scientific discovery.
Such reasoning has a strong pragmatic character and is transacted with comparatively scarce cognitive assets. The question is how to get technology to reliably replicate this? The need for such technology is pressing. Paradoxically, the information explosion is leading to diminished awareness. Expertise is becoming ever more specialised: individuals, groups, communities, enterprises are consequently becoming increasingly insular.
We need computational systems which have the capability to enhance our awareness, for example, by suggesting associations in context that we could make, but increasingly don't, as we generally lack the cognitive resources to do so. We believe that information processing technology has to manipulate context sensitive meanings which accord with those we harbour.
In other words, the "meanings" manipulated by the technology should be cognitively motivated. This point of departure readily gives rise to the question of how to get access to the meanings we carry in our heads and have technology manipulate them to good effect.
The field of cognitive science has recently produced an ensemble of models which have an encouraging, and at times impressive track record of replicating human information processing, such as human word associations norms. For example, primed with the word "Beatles" a common associate produced by human subjects may be "band", or "John Lennon". These models are generally referred to as "semantic space models". The term "semantic" derives from the intuition that the meaning of a word is derived from the "company it keeps'', a famous quote originally from the linguist J.R. Firth (1890-1960).
For example, the words "mobile" and "cellular" would exhibit a strong association in semantic space as the distribution of words they co-occur tends to be similar, even though the two words almost never co-occur themselves.
Although the details of the individual semantic space models differ, they all process a corpus of text and "learn" representations of words in high dimensional space. That is, the meanings of words are given a geometric representation. Semantic space models are interesting in light of the scenario presented above as they open the door to gaining some operational command of the meanings we carry around in our heads together with mechanisms to replicate our ability to draw relevant context-sensitive associations.
One of the big questions is how to effectively model the interplay between meaning, context and such human pragmatic inference mechanisms. Surprisingly, quantum mechanics may provide some innovative and ground breaking inspiration in relation to this challenging question.
Recently a highly speculative but potentially far reaching discovery was made by the theoretical physicist Diederik Aerts and his collaborators. In a letter to the editors of a journal dealing with mathematical physics, they showed the formalisation of quantum mechanics (QM) shows very strong connections with the mathematical basis of semantic space models.
What are the implications of this intriguing connection given that semantics space models have an established track record of cognitive compatibility with human across a variety of information processing tasks?
In order to provide some intuition about how QM relates to human semantic space, consider the word "suit". In isolation it is ambiguous - it may refer to an item of clothing, a legal procedure, or even a deck of cards. However, when seen in the context of words such as "wore" or "grey", the ambiguity resolves into the sense of the word dealing with clothing.
The connection with QM is the following. Consider an electron moving towards a TV screen. Before it impinges on the screen it is a set of potentialities, that is, a collection of all the possibilities of hitting each and every place on the screen. In other words, before impingement, all these possibilities are "superimposed". The quantum state includes all of them, and then, in the atemporal process of quantum collapse, one of the possibilities is singled out and becomes actual - the electron impinges at a specific location on the screen.
Now going back to our example word "suit". In human memory the meaning of this word is like the electron in the following way. In the past, this word has been seen and heard in many circumstances, for example, "John wore a grey suit", Thjese become superimposed in human memory as different potential meanings, or senses, of the word "suit". When we see the word "suit" in the context of other words, i.e., its "company", the superimposed potential meanings of this word "collapse" onto a specific one. At that point the meaning is resolved which is akin to the electron becoming actual at a specific location.
Human beings do this effortlessly, which may suggest the process is happening below the symbolic level of cognition. This raises the speculation that something like a quantum logic operating on semantic space may provide the sought after model capturing the interplay between meaning, context and human sub-symbolic reasoning mechanisms. (The author was recently awarded a three-year grant from the Australian Research Council to pursue this line of research.)
Some may view this is as drawing a very long bow, and QM can only ever being used as an analogy. It would be misunderstanding to assume QM has anything to do with something physical. Strident philosophical debate aside, QM is an abstract framework. It is the responsibility of a specific theory at hand to plug into it, and then the handle of the abstract framework is cranked.
As it is an abstract framework, this opens the door for its application outside of physics, and in recent years QM has increasingly permeated other areas. In March, 2007, the first Quantum Interaction symposium will be held drawing together for the first time researchers from all over world who are using QM outside of physics. Presentations will be given detailing how QM interacts with logic, artificial intelligence, meaning, cognition, search, and even finance ("Quantum Econophysics"). It is very significant the highly reputed and distinguished philosopher of science, Emeritus Professor Patrick Suppes (Stanford University) agreed to present an invited talk on QM and the brain. This shows that speculation about quantum effects in the brain has some serious traction way beyond the circle of new age literature. Some, perhaps many, physicists may frown on such developments and deem it an abuse of QM.
Time will tell whether a "deep result" using QM outside of physics is possible. The author has an open mind and believes it just may be possible. It could be such a result may manifest in relation to human memory.
Professor Douglas Nelson will present a paper at the Quantum Interaction symposium titled "Entangled associative structures and context". After extensively studying human word association norms for over 30 years, he puts forward the intriguing hypothesis that word associates in human memory behave like particles exhibiting quantum entanglement. Quantum entanglement is when a measurement on a particle, e.g., measuring its position, causes the instantaneous quantum collapse of another particle even though they may be separated by an astronomical distance.
When a human subject is cued by a word in a memory experiment, the probability they will recall a target word depends on the number of links between its associates. By way of illustration, say the cue word is "planet". There is a probability that the word "earth" will be recalled. In memory, "earth" has a link with "moon", but there is no link back from "moon" to the cue word "planet" as this word is not typically recalled when subjects are cued with the word "moon". (After all, the moon isn't a planet) The "earth - moon" link nevertheless contributes to remembering the word "planet".
Nelson refers to this as "spooky action at a distance", the intuition here being that "moon" and "planet" are distant as, in memory, there is not a directed link from "moon" back to "planet". Nelson argues that such findings are inconsistent with widely held views in psychological science and support the incorporation of quantum mechanics in our attempts to understand how prior knowledge interacts with recent experience and context.
A quantum logic
February 19, 2007

Small drops to put out large fires

www.innovations-report.de
Russian scientists are developing a mathematical model of both the fire itself and the technology needed to fight it that uses disperses water.

As a result it will be possible not only to gain a thorough understanding of the processes that occur with microscopic water droplets in the zone of the fire, but also to select optimal, that is the most effective and economical, means to put out a fire. Information support for the project comes from the International Science and Technology Centre, whose specialists found the project to have immense potential.
At the heart of the project, which involves the work of specialists from the All-Russia Research Institute of Experimental Physics (Sarov) and their colleagues from the St. Petersburg State Polytechnic University, lies the use of sprayed water where the individual droplets are about 100 microns in size. While it may seem strange to the layperson that such small droplets could put out a blazing fire, the specialists are in no doubt at all. Its advantages are in the following.
An aero-suspension (aerosols or droplets in air) has an immense specific surface, so the burning zone rapidly cools. The volume of the dispersed water cloud, too, is an order greater than from a jet of water of the same mass. Therefore the efficiency coefficient or, more specifically, the coefficient of water use, is tens of times higher as compared with a usual jet, even if such a jet is both powerful and precisely directed. Furthermore, in the event of a forest fire, for example, when the area of coverage is very large, it is practically impossible to cope with the fire with individual jets or with a localized strike per se; while pouring on water in one place, the fire flares up in another. In addition, the damage caused to a building by putting out a fire is comparable to the damage from the fire itself, while a mist would be very unlikely to even affect electronic equipment.
In theory, there is no doubt that the method has considerable promise. However, in practice things do not always turn out so simply. To ensure the method really is effective, a multitude of factors have to be borne in mind. These factors include the correlation between the specific power of the focal point of the burning and the sizes of the space to be protected, the size, concentration and rate of movement of the droplets, the intensity and duration of the process of extinguishing the fire for different fire fighting systems that use fundamentally different means of obtaining the active material and many others.
Furthermore, serious theoretical studies are needed, relative to the formation and the behaviour of water droplets at high temperature, and to the parameters of gas flows in the area of the fire and in its direct vicinity. The fact is that the high efficiency of this method is conditioned by the fact that dispersed water rapidly cools the zone of the burning, while water vapour forces out the oxygen from it. This is the so-called phlegmatization method, in part resembling how fire is covered with a thick blanket, only here a cloud of mist covers the entire zone of the fire at once, depriving the fire of heat, air and, finally, its very life. However, this is of course if the dispersed water reaches the zone of the fire, and in the sufficient quantity. Therefore, conditions have to be created so that its convection flows were as if drawn into the area of the fire before the minute droplets can evaporate from the heat or before they are carried away by a flow of hot gases.
Mathematical modelling helps the scientists to cope with such complicated and multiple-factor research. They have already achieved serious success in developing the mathematical model of certain processes that occur during the burning and extinguishing of fires with dispersed water. However, virtual experiments alone are not enough for a complete solution of the set tasks; what are needed are genuine, full-scale experiments, as it is these that will enable the more precise definition of the numerical model and the final determination of the optimal means for putting out a fire with dispersed water.
VNIIEF has the required conditions, that is, a testing ground, where such experiments may be conducted. However, unfortunately it is not yet sufficiently equipped with the requisite equipment, such as IR sensors that would enable rapid measurement of temperature in any point, both in the very focal point of the fire and in the space around it. Yet the scientists know for sure what equipment they need and they are confident that, with the required financing, they could develop the technology to help put out a fire rapidly, effectively and as safely as it could possibly be done. The guarantee of success lies in the colossal experience and knowledge that is available.
Small drops to put out large fires

February 12, 2007

Viet Nam's mathematical superstar

vietnamnews.vnagency.com.vn
Professor Tuy
Fellow researchers: Tuy poses with Russian mathematician
L.V. Kantorovitch,
1974 Nobel Prize winner in economics. — File Photos
Professor Tuy
Passing the torch:
Professor Tuy still teaches in the capital.
(04-02-2007)
Professor Hoang Tuy's theories revolutionised economics and market planning. Ham Chau reports on his remarkable life.

I came to Hoang Tuy's home on Ha Noi's Doi Can Street on a winter day in late 2006. The professor, now 79-years-old and beholden to a hearing aid, received me with a big smile.
Tuy is considered one of the fathers of optimisation theory, a mathematical technique designed to find the best possible outcome given a series of constraints. The theory is considered a cornerstone of modern economics and credited with clearing the muddy waters of everything from long-distance transport to rice growing. So it should come as little surprise that some of the world's top mathematicians and programmers will celebrate Tuy's 80th birthday when they gather in Rouen, France, a little under a year from now.
Tuy was born on December 12, 1927 to family of Confucian scholars in Xuan Dai Village, located in the province of Quang Nam. The family was well known thanks to the brother of his grandfather, Hoang Dieu (1832-1882), a northern provincial leader who killed himself when the fort of Ha Noi fell to French invaders.
The family was also renowned for its scholarly achievements. One of Hoang Tuy's brothers, Hoang Kiet, became a famous artist while two others, Hoang Phe and Hoang Chung, are accomplished professors.
In his early childhood, Tuy was the top student in his village school, excelling in both math and literature. A young Tuy was eventually sent to the famous Quoc Hoc School in Hue for secondary studies. There, while he still topped his class in both subjects, he began devoting more time to mathematics.
At the age of 15, he was stricken with a severe bout of pneumonia that left him partially paralysed. Thanks to treatments from a local acupuncturist he recovered, but had to leave Quoc Hoc and join a private school. In 1946, despite all the difficulties, he topped national high school examinations and travelled to Ha Noi to attend the College of Sciences.
Unfortunately, war broke out and forced him to return home. But before he left, he criss-crossed Ha Noi in search of mathematical texts. In 1951, he was teaching in a resistance zone when he learned that renowned professor Le Van Thiem was returning to Viet Bac, located in mountainous northern Viet Nam, from Switzerland. He immediately asked the local Department of Education for permission to travel to Tuyen Quang, the capital of the resistance government, to meet the eminent professor. At the time, the route along the Truong Son Range was still very much a small mountain path amidst the jungle unlike the later famous Ho Chi Minh Trail.
After receiving the go-ahead, an enthusiastic Tuy set off, bringing along only rice, water, his mathematical books and anti-malarial drugs. Travellers along the route face constant threats from French ambushes, tiger attacks and disease carrying mosquitoes.
It took Tuy almost six months of walking before he arrived in Tuyen Quang, only to learn that the professor he sought had already left for China. So, he decided to extend his trip. After crossing the border into China, he headed for Naning, where he joined other Vietnamese students.
When Ha Noi was liberated in 1954, he returned and was appointed lecturer at the College of Sciences. In July 1957, he was among the first eight scientists sent to the Soviet Union for post graduate work. He spent just over a year completing his doctorate thesis, a surprisingly short period of time for a man who studied almost by himself.
In 1997, as he approached his 70th birthday, the Swedish LinkoŠping University's Institute of Technology held a three-day seminar under the banner "Optimisation – From Local to Global" in honour of Tuy. A publishing house released the workshop's proceedings, which were gobbled up by international scientists. Tuy's reputation as the father of global optimisation had been born.
Today, most mathematicians in the world acknowledge his contributions, which include Tuy's Cut, Tuy-type algorithms and Tuy's inconsistency condition to name a few.
In September 2002, the Operation-Research Bulletin, the forum of Asia-Pacific operations mathematicians, published a special issue on Tuy that included articles by several eminent scientists. Tuy also co-authored Global Optimisation – Deterministic Approaches. The book was first published in 1990 and then revised in 1993 and 1996. It is considered by many as 'the Bible of optimisation'. Apart from the books, he is also the author of some 140 internationally recognised studies.
Today, Tuy still works tirelessly for the Institute of Mathematics in Ha Noi and continues to assert his great influence in the world of optimisation. He has received many prestigious awards from the Government of Viet Nam for his dedication and contributions to the country's development, including the Ho Chi Minh Award. — VNS
Viet Nam's mathematical superstar

February 12, 2007

Influential Statistician to Speak at Carleton College

apps.carleton.edu
Scott Zeger
Scott Zeger,
Johns Hopkins University
Bloomberg School of Public Health

Professor Scott Zeger, chair of the department of biostatistics at the Johns Hopkins University Bloomberg School of Public Health, will deliver a talk entitled "When Counting is Not as Easy as 1, 2, 3: Iraq Mortality Since the U.S. Invasion" at Carleton College on Tuesday, Feb. 13 at 3:30 p.m. in Olin Hall, room 149. The lecture is free and open to the public.
In October 2006, The Lancet, a highly-respected British medical journal, published a study estimating that close to 650,000 Iraqi civilians have been killed since the March 2003 U.S.-led invasion of Iraq. Zeger was an advisor to the study, which was conducted by researchers at the Bloomberg School along with Iraqi physicians. The study sparked significant controversy, despite its approval by many other statisticians and public health officials. President Bush, however, suggested that "The methodology is pretty well discredited."
Zeger is the Hurley-Dorrier Professor and Chair of Biostatistics at Johns Hopkins Bloomberg School of Public Health. He received his BA in biology from the University of Pennsylvania and his PhD in statistics from Princeton University. Zeger is a Member of the National Academy of Sciences Institute of Medicine and Fellow of the American Association for the Advancement of Science and the American Statistical Association. He is co-editor of the Oxford Press journal Biostatistics and a member of the Springer-Verlag editorial board for statistics. He was awarded the 1987 Snedecor Award (with co-author Dr. Kung-Yee Liang) for the year's best paper in biometry. The American Public Health Association recognized Zeger in 1991 with the Spiegelman Award for contributions to health statistics. In 1987, 2002 and 2005, the Johns Hopkins Student Assembly awarded him the Golden Apple for excellence in teaching. Science Watch notes Zeger as one of the top 25 most-cited mathematical scientists of the past decade.
Zeger's appearance is sponsored by the Carleton math department and the QuIRK (Quantitative Inquiry, Reasoning, and Knowledge) initiative. QuIRK is an innovative project intended to help Carleton and other institutions of higher education better prepare students to evaluate and use quantitative evidence in their future roles as citizens, consumers, professionals, business people, and government leaders.

For more information, contact the math department at (507) 646-4360.
Influential Statistician to Speak at Carleton College

February 12, 2007

Math models add more options for life sciences, cancer researchers

newsinfo.iu.edu/
Santiago Schnell
Santiago Schnell
Feb. 8, 2007
BLOOMINGTON, Ind. -- Imagine being able to take a fantastic voyage into the human body and see how life evolves in a single cell, observe what triggers and sustains a beating heart -- or perhaps journey into a tumor to witness how cancer destroys life.
Such a possibility is not the stuff of overactive imaginations or sci-fi films; it's the domain of Assistant Professor Santiago Schnell, who heads the Systems Biology Laboratory at the Indiana University School of Informatics. Systems biology offers a multidisciplinary approach to studying biological phenomena by integrating research techniques and methodologies from biology, chemistry, physics, engineering, mathematics and computer science.
This collaborative endeavor uses mathematical modeling to better understand the origin and progression of life systems. And that approach is explained in large part in "Multiscale Modeling in Biology," featured in the March-April issue of American Scientist. Schnell, the principal author, is joined by Ramon Grima, of London's Imperial College; and Philip K. Mani, of the University of Oxford.
"Firmly rooted in observation and experiment, biology for decades had little use for mathematical modeling, which was, in any event, a slow business until computers made it possible to simulate large complex systems of nonlinear equations," said Schnell, assistant professor of informatics, who holds adjunct appoints in physics and biology.
"Today," Schnell added, "biologists and mathematicians desperately need one another -- not just to find structure in the vast quantities of data flowing from experiment but also to integrate this information into models that explain at multiple scales of time and of space how life works."
Schnell and his colleagues have numerous ongoing research projects using multiscale modeling. One endeavor, funded by the National Institutes of Health, studies how early embryo-made segments form blocks of cells that are precursors of the vertebrate. Failures in segmentation can be fatal or can cause developmental abnormalities such as scoliosis and spina bifida.
Schnell also has been working on a modeling project based on genetic and molecular features of the evolution of colorectal cancer and the effectiveness of treatments. The study appeared in Theoretical Biology & Medical Modelling a year ago and has garnered much attention from cancer researchers and scientists. This work is ranked first among the most viewed articles of all time in the journal.
"We now have a good deal of information about the genetic mutations underlying colon cancer and how activation of the mutated genes is affected by oxygen starvation and overcrowding," Schnell said. "We can model the life cycle of a cell in its various stages and how it is influenced by environmental changes."
More specifically, they are constructing a model to predict what proportion of cells would be sensitive to radiation therapy at different stages of tumor evolution. Currently, radiation is administered to cancer patients using extensions of a 20-year-old model that assumes tumor sensitivity and population growth are constant during radiotherapy.
"We found that radiation doses administered to stressed cells are effective, but radiation administered after the tumor reaches an oxygen-starved condition has little effect because most of the cells have become inactive," said Schnell.
Mathematical modeling of biological systems, including cancer, poses challenges on several fronts, Schnell said. The first is to ensure the collection of qualitative and quantitative experimental observations, and that requires closer collaborations with scientists from several disciplines. A second task is to construct a model that has a reasonable amount of precise parameters to simplify a problem without losing its essentials.
"The use of mathematical ideas, models and techniques is rapidly growing and increasingly important throughout life sciences," Schnell observed. "The development of new programs has eliminated the well-demarcated divisions between theory and experiment. The culture of biology is changing with a growing awareness that, as a colleague recently told me, 'to think is to model.' "

More information about the Systems Biology Laboratory at the IU School of Informatics is at http://www.informatics.indiana.edu/systemsbiology. To arrange an interview with Santiago Schnell or to receive a copy of the American Scientist article, contact Joe Stuteville at 317-946-9930 or jstutevi@indiana.edu.
Math models add more options for life sciences, cancer researchers

February 12, 2007

Big Sky graduate an emerging star in science field

www.missoulian.com
By ROB CHANEY of the Missoulian
The back halls of Big Sky High School are a breeding ground for curiosity.
Senior Samantha Lidstrom is blasting tiny sailboards across a lake of ball bearings in a blue wind tunnel. Classmate Amy Smith is unraveling the genetic codes of phycobilisome, which sounds like a hillbilly bar band but is really a cyanobacteria strain found in hot springs. Science teacher Jim Harkins wanders among the work stations, inspecting vector equations and rocket engines.
"I try to tell the kids that what we're doing here is not really science," Harkins said. "I'm doing my best to stimulate their curiosity. Science is not learned in books while sitting at desks."
Half a continent away, a former student of Harkins' is sitting at a desk at the University of Toronto, where he's a visiting research scientist in number theory. His name is Jayce Getz, and last week he was awarded one of 30 National Science Foundation mathematical sciences postdoctoral research fellowships. The trail of his success leads back through Harvard University to Big Sky's back hallways and the science rooms at Target Range Elementary School.
"Kids in Missoula, Montana, can and do get involved with important research in the sciences," Getz said in a phone interview. "The trick is to get started early on."
Getz, for one, did just that and Harkins played a part in it.
Harkins is in his 24th year teaching science in Missoula. Most of that time, he's offered an Advanced Problems in Science class, which guides students through independent study projects. Its goal is to produce research papers. But its real target is training students how to explain and demonstrate their discoveries in public - particularly in science fairs and competitions.
Moving science and math outside the classroom and into a social world was a major motivator for Getz.
"The science fair experience is incredibly important," Getz said. "The sooner you get involved with something close to real research, the better. And making contacts with professionals is absolutely crucial."
In his case, one of his Big Sky teachers was Robin Anderson, who had a son-in-law named Ken Ono. Ono is the Manasse professor of letters and science at the University of Wisconsin in Madison, and Getz's doctoral thesis adviser. He has mentored several other Big Sky students whose scientific ambitions were fired by science fair experience.
What Getz is doing these days even his own mother is at a loss to explain. It's a branch of number theory called "intersection theory and modular forms." Getz suggested it's kind of like finding a dinosaur's foot and being able to understand what its whole body looks like. Or put more practically, it's the science that underpins how the sound of your voice can be digitally deconstructed and reconstituted between one cell phone and another.
And at the moment, it's the basis of what Ono called "the most important Ph.D. thesis in number theory this year" out of more than 1,000 such research efforts. It has already earned Getz the Veblen assistant professorship from Princeton University's Institute for Advanced Study. He'll start that three-year position next fall.
"I was really lucky that things worked out the way they did, and that my parents were really supportive," Getz said. "At the same time, these opportunities do exist, and kids should take advantage of them. If a teacher says, 'I don't know how to do it,' keep asking."
In the Advanced Problems in Science lab, Lidstrom and Smith are preparing to take their own steps into the scientific research world. Lidstrom is using that blue wind tunnel to test sail designs. She's found that traditional triangular models tend to be the most efficient, but newer curvy shapes give better lift for jumps.
"I'm actually not a windsurfer, so this is kind of new for me," Lidstrom said. "But it's really interesting. I like to figure out how things work."
Smith is already a veteran of four science fairs with her phycobilisome, which she pronounced "psyco-billy-some."
"I love saying that word," she laughed. "The science fairs really revive your spirit. You get to see what opportunities are out there, and who's doing what."
For Harkins, the trick is matching the student to the discipline. The back hallway is a corridor linking several of Big Sky's science labs. Teachers love it, he said, because they can set up shared work stations and see what their colleagues are up to.
"We strive to keep a large number of electives here, so kids can have lots of options," Harkins said. "If we just offered biology and chemistry and physics like some schools do, many kids might never open that door. My philosophy is to have fun. If it isn't fun, what are we doing here?"
Big Sky graduate an emerging star in science field
February 12, 2007

South Africa: Street Dogs - Earthquakes Can Teach Us About Market Moves

allafrica.com
(Johannesburg)
Business Day COLUMN
February 7, 2007
Posted to the web February 7, 2007
Michel Pireupireum
Johannesburg
THE stock market has its share of shake-ups, but who would guess that large movements in this man-made system adhere to a similar pattern of predictability as earthquake magnitudes? Researchers at Boston University and the Massachusetts Institute of Technology have found that stock prices follow a distribution that is almost identical to that of earthquakes. "Financial earthquakes and natural earthquakes are perfect analogues for one another," says Dr Eugene Stanley, director of the Centre for Polymer Studies at Boston University, who performed the research with Dr Xavier Gabaix, a professor of economics at MIT.
While some have suspected for years that stock market fluctuations follow a power law, the new research shows that stock indices in Hong Kong, Tokyo and Europe all follow the same law.
The patterns found by the scientists are "power laws" that describe mathematical relationships between the frequency of large and small events. One such power law is used to forecast the chances that an earthquake of a given magnitude will occur.
In short, the scientists have shown that stock markets have a mathematical elegance frequently found in natural systems.
As Gabaix explains: "We have found that the artificial world of the financial markets follows a pattern similar to one found in our natural world. Trading on the stock market has a lot of randomness but at the end of the day you find that a pattern emerges that matches power law patterns found empirically in data from systems as diverse as earthquakes and human language."
The team also found that the actions of large market participants, such as mutual funds, produce this power law behaviour when they trade stock under time pressure. "We want to understand financial earthquakes in order to protect people like you and me, whose retirement is tied up in the markets," says Stanley. "In Tokyo they build buildings so that they don't succumb to earthquakes. We need to do the same thing in economics.
"But our research suggests that the forces that give rise to the power laws of stock market fluctuations are extremely robust," says Gabaix. "So unfortunately, such crashes would be very, very hard to prevent.
"When applied to a precise computer model, the power laws might allow market analysts to predict a crash, but not necessarily prevent it.
"We believe that the computer model presently used by most analysts undercounts the number of large, rare events. That is what we're looking at next," says Gabaix. "If we combine physics methods and economic reasoning, we may be on the right track."
South Africa: Street Dogs - Earthquakes Can Teach Us About Market Moves
February 12, 2007

Making math sound easy

morningsentinel.mainetoday.com
By BETTY JESPERSEN
Staff Writer
When two math guys decided to collaborate on writing an engaging, easy-to-understand book on the history of mathematics, they turned to the popular fantasy book "Harry Potter."
"I wanted to get a feel for what is readable," said Fernando Gouvea, Colby College's Carter professor of mathematics and the author of research papers such as "Arithmetic of Diagonal Hypersurfaces over Finite Fields," with fellow mathematician Noriko Yui.
"My wife was reading 'Harry Potter' at the time, and I copied two paragraphs just to get the feel for what the sentences sounded like," said Gouvea, of Waterville, an affable professor who says his first love is number theory.
What immediately jumped out were the short sentences. In the world of mathematics, sentences are long, involved and peppered with dependent clauses, he said. For many readers, particularly those without a math background, it is daunting stuff.
Gouvea and his Colby colleague, William Berlinghoff of Farmington, worked for two years researching and writing a history of mathematics that could be understood by high school and college students and picked up by anyone curious about the history of mathematical ideas.
Their efforts have been recognized.
Their 260-page book, "Math Through the Ages: A Gentle History for Teachers and Others," earned them the Beckenbach Book Prize from the Mathematical Association of America. The honor includes a $1,000 cash prize.
Tina H. Straley, the association's executive director, said the book was recognized because it has wide appeal and is beautifully written.
"The wonderful book is at a level that is approachable and very interesting to readers of mathematics, be they mathematicians, students of mathematics, or those who are fascinated by the subject," she said during a telephone interview recently.
Published jointly by Oxton House in Farmington and the association, first in 2002 and in an expanded edition in 2004, the book is used as a textbook in colleges and in middle and high school classrooms across the country. It is already in its third printing.
Berlinghoff noted it has also been discovered by a public intrigued with books that trace the beginnings of such world-changing concepts as zero and longitude.
The prize is not awarded on a regular basis but is given only when a book appears on the scene that is truly outstanding, according to the math association. The Mathematics Association of America is the world's largest professional society that focuses on making mathematics accessible at the undergraduate level.
"Math Through the Ages" is organized into 25 "sketches," each between four and six pages long, that summarize centuries of development of the most important topics in general mathematics.
They range from concepts such as the history of arithmetic and algebra through modern topics such game theory, statistics and computing. There is also a 54-page mathematical "history in a nutshell," a discussion of historical books and Web sites and an extensive bibliography. The expanded edition includes classroom exercises and projects.
"We thought up the idea of the small sketches so the book could be picked up by someone who wanted to find out, in four pages, where did zero come from, but didn't have the time to pull out all the references to the history of zero," Gouvea said.
Berlinghoff, also a folk singer who plays guitar and banjo in area restaurants and coffeehouses, has devoted much of his career to developing math curriculums for high school students.
"I had been complaining about high school math preparation for years and felt it was time to put my efforts where my mouth is," he said. "I wanted to get (students) to understand that mathematics has a human side, an historical side and an aesthetic side."
Mathematics has been a part of human development for thousands of years, he said. "It is only the way it is taught that appears isolated. I am trying to break that isolation and one way to do that is to look at history."
"For me, this book is the culmination of many years of trying to transmit a sense of the humanity and charm of mathematics to elementary and high school teachers and through them, to their students," Berlinghoff said.
One of the mathematics association's requirements for the prize was that the authors communicate their ideas clearly, Berlinghoff said.
"The book appealed to the committee because it tells the stories accurately and tells them well. The book was an enjoyable, instructive, sometimes humbling, collaboration, with Fernando's meticulous scholarship counterbalancing my enthusiasm for simplicity," Berlinghoff said.
Berlinghoff said he was delighted with the Bechenbach Book Prize.
"It is a big deal," he said. "Our book was originally written as a resource for teachers and it was not our intention to market it to the general public. But the fact that other people appear to like it is very gratifying."
Gouvea said when Berlinghoff first suggested the collaboration, he had no idea how much fun it would be.
"We argued about history, delved into original sources and complained about and improved upon each other's sentences," he said. "Bill's understanding of our potential audience played a crucial role in toning down my tendency towards the highfalutin'."
Gouvea, who said he has been fascinated with numbers since he was a boy in Brazil, said the first step to conveying excitement about a topic is to get excited about it yourself.
"That is one of the things history can do. It can turn you on a little bit and once you are turned on, it is much easier to get students to see that there is something here that is exciting," he said.
"They might decline to follow but at least they'll see I'm not just going through the motions -- I really care."

Betty Jespersen -- 778-6991
bjespersen@centralmaine.com
Making math sound easy

February 12, 2007

Invest in maths or suffer brain drain, Govt told

www.abc.net.au
A leading academic from the Australian Academy of Science says the nation is facing a devastating brain drain of teachers and students of mathematical sciences.
Professor Hyam Rubinstein will tell a forum in Canberra today that Australia is at risk of losing its international competitive edge in areas such as innovation unless it invests more in the subject area.
He says one of the big problems is the low amount of funding for mathematical sciences at universities.
"Just to make that very specific, that we get about $5,000 a student from the Federal Government, whereas in engineering and physical sciences, it's around $12,000 a student," he said.
Professor Rubinstein says there has been a severe decline in the number of students and lecturers at universities' maths departments.
He says in the last decade, one third of permanent academic staff positions in the area of mathematical sciences have gone.
"There are very, very few academics under 40 in the mathematics and statistics departments," he said.
"I think with the retirements coming up and with the financial squeeze on departments, if we don't get relief I really fear for the consequences."
The International Council for Industrial and Applied Mathematics has echoed Professor Rubinstein's concerns, and has issued a review of the industry ahead of today's forum.
It warns maths research is becoming increasingly narrowly focused in Australia, and university courses such as economics no longer have a strong maths component.
It also says there are not enough trained maths teachers in high schools.
Invest in maths or suffer brain drain, Govt told
February 12, 2007

Girls do the math

www.rutlandherald.com
February 12, 2007
By Brent Curtis Herald Staff
Whoever said girls aren't good at math should watch 13-year-old Kate Candon of Rutland in action.
One of more than 100 sixth- through eighth-grade math whizzes who competed on Saturday, Candon distinguished herself by taking second place in the individual countdown round of Mathcounts — a mathematical contest akin to a spelling bee.
There were 107 contestants and at least that many parents, family members and coaches crowded into a lecture hall at Castleton State College during the countdown round.
But despite the noise and the pressure of facing ever more daunting mathematical challenges during the elimination-style contest, Candon, a student at Rutland Middle School, kept her cool.
With calculated precision, she crunched complex formulas in her head while many of her rivals frantically scratched for answers on sheets of paper. Before most of her challengers had an answer — and sometimes before coordinator Paul Cipriani had finished reading the question — Candon was hitting her buzzer with the right answer.
"I like numbers because there's not really an opinion to them. There is a right answer and a wrong answer," she said shortly after falling to Neil Guertin, a seventh-grader from Middlebury, who beat Candon by a score of 1-0 in the final round of the competition.
"I do 90 percent of the calculations in my head and I do them as fast as I read the question. I got nervous though. I was shaking by the end," she added.
Asked what she thought of studies that have indicated that girls typically struggle more than boys to achieve at math, Candon didn't need many words to give an opinion.
"Not true," she said.
Her math coach, Middle School teacher Tad Tucker, said his student's success reflected a lot of hard work in the classroom.
"I shouldn't say I'm surprised because I know how hard she works," he said. "It's really awesome what she achieved today."
Candon wasn't the only Rutland student to do well during the competitions, which consisted of students from Bennington, Rutland and Addison counties.
The four sixth-graders who made up the Rutland Intermediate School team took second place for team records, finishing behind Middlebury Middle School, which finished first, and ahead of Mt. Anthony Middle School in third.
The Intermediate School team comprised students Alexis Calcagni, Liam Clark, Andrew DeWolf and Joshua Wight. Intermediate School math teacher Joshua Bunker coached the team.
The number of students participating in this year's Mathcounts competition was the most that Cipriani said he's seen.
"I couldn't believe how packed it was in there," Cipriani said, describing the 200-seat lecture hall where people stood and sat in the aisles for lack of room. "Just three years ago, half those seats would have been empty."
For many observers in the room, the complex questions and their answers were hard to fathom.
Still, Kate's father Kevin Candon said he was engrossed by the competition.
"Some of the questions were mind-boggling, but it was terrific," he said. "I was nervous watching her. I think she was calmer than I was."
Winners in Saturday's Southwest regional Mathcount competition are eligible to advance to the statewide competition taking place later this year. Winners in the state competition can compete in Mathcount national competitions being held in Texas this year.
Girls do the math
February 12, 2007

Ambitious filing clerk sets new digit-memorizing record

www.uecrescent.org
Tom Avril • The Philadelphia Inquirer
Friday, February 09, 2007
(MCT) PHILADELPHIA—Remember pi? Most of us learned the 3.14 part.
But Marc Umile has gone oh-so-much further.
Umile was certified as the North American record-holder for memorizing digits of the mathematical constant last month. He spewed out 12,887 digits, to be exact—a feat that took him 3 hours and 40 minutes.
For those whose math skills are a little fuzzy, pi is the ratio of a circle's circumference to its diameter.
It begins with 3.14159 and never stops or repeats the same pattern, captivating both number buffs and those looking for a deeper mystical meaning.
Umile wrote the numbers out by hand, 1,000 at a time, then recorded them on a portable tape player.
Then, he listened. And listened some more. During his commute. During his lunch break. While walking down the street.
After two years, two worn-out tape players and more than 100 batteries, it sank in.
He does not profess to be a math whiz. A filing clerk for a company that handles Medicare bills, he never studied trigonometry and did not attend college. Yet it is clear he has a passion for numbers and puzzles, not to mention a relentless determination and the ability to ignore those who thought he was a little strange.
He found the world-record list on the Internet one day and saw Asians and Europeans dominated it. He decided the United States needed another representative.
"It seems like in the Eastern part of the world, they really have their stuff together," Umile said. "I want to help us catch up."
Umile set the record in December 2006 at the law office of Montgomery McCracken in front of three witnesses. He did not recite the numbers out loud, but typed them into the computer, 1,000 at a time, after which the witnesses verified their accuracy by using a spreadsheet.
"It's just an amazing accomplishment," said Philadelphia real estate agent Warren Nelson, one of the witnesses.
The necessary forms were mailed to Germany and the performance was certified by Jan van Koningsveld, himself a top competitor in international contests of mental gymnastics, who maintains a web site that lists pi record-holders for each continent and for the world.
Umile is far short of the world record of 43,000 that van Koningsveld cites on his list, held by Krishan Chahal of India. He is even farther from the 67,890 digits listed by the Guinness World Records, a feat accomplished in China.
But he does hold the world record for memorizing 905 digits of "e"—another key mathematical constant—which he recited on the same day as pi. And three months earlier, he notched another world record by doing the first 5,544 digits of the square root of two.
© 2007 The Philadelphia Inquirer
Ambitious filing clerk sets new digit-memorizing record
February 02, 2007

Hungarian scientific discovery makes waves

www.caboodle.hu
monomonostaticbody
A homogeneous, convex body
with just two balance positions (top)
and as it appears in nature
on the shell of an Indian Star Tortoise
(bottom)
For the first time since 1979, a Hungarian scientific discovery is featured on the front page of the respected international journal Mathematical Intelligencer.
Twenty-eight years after a Rubik's Cube appeared on the cover, Hungarian mathematicians have solved a geometric theorem produced by a man considered by many to be the greatest living mathematician, Russian V. I. Arnold.
Arnold's conjecture" is that bodies with less than four balance positions, or equilibria, might exist. Hungarian scientists Péter Várkonyi and Gábor Domokos have discovered homogenous objects with only one stable and one unstable position. In their paper, they write that such forms appear in nature due to their special mechanical properties. Their research helps to explain the shape of tortoise shells, in particular, the distinctive Indian Star Tortoise.
Várkonyi was a silver medalist at the 1997 Student Olympics in Physics, while Domokos is the youngest member of the Hungarian Academy of Sciences. They both teach at the Department of Architecture at the Budapest Technical University. Domokos has been a visiting scholar at the universities of Maryland and Cornell.
Várkonyi is currently a post-doctorate scholar at the University of Princeton.

Related Links:
Original story (fn.hu, in Hungarian)
Mono-monostatic Bodies: The Answer to Arnold's Question (Paper by P. L. Várkonyi and G. Domokos, in English)

Hungarian scientific discovery makes waves

February 02, 2007

Exhibit in library displays many sides of turtles

media.www.ramcigar.com
Turtles
Media Credit: Rebecca Laferriere
URI physical education instructor Tony Monahan
has created an exhibit titled "Carapace Awakening"
which is being held in the URI Library Gallery.
In a press release about his works, Monahan said,
"Artistically, I see and construct the world through the use of turtles,
which manifest themselves in various designs and patterns."
The exhibit is open to the public from Jan. 22 to March 1.
Turtles
Media Credit:
Rebecca Laferriere
Robert Preliasco
01/25/07 - Turtles in space. Turtles on the sun. Turtles in nature. And turtles in math formulas.
These scenes and more are part of an exhibit now on display in the University of Rhode Island's Library Gallery.
URI physical education instructor Tony Monahan created 20 acrylic paintings and framed paper sculptures, using turtles to portray nature and world culture. In fact, all of Monahan's art currently on display is inspired by his lifelong fascination with the hard-shelled creatures.
"I make no excuses," Monahan said in a press release. "It's all about the turtles."
Monahan created the works on display between 1999 and 2006.
"Artistically, I see and construct the world through the use of turtles, which manifest themselves in various designs and patterns," Monahan said.
Many of the artworks, such as the paper sculpture "Balance," represent different cultures. The sculpture shows a Yin Yang comprised of two turtles.
Another sculpture, "Turtles All the Way Down," shows the Earth on top of a seemingly infinite stack of turtles. The concept of the Earth on the back of a turtle has its origin in several Native American creation myths.
One of the central pieces of the exhibit is "The Fibonacci Procession." The Fibonacci sequence is a mathematical phenomenon found in all aspects of nature.
Monahan used the actual mathematical formula to create the sculpture, which has been displayed in the Newport Art Museum.
Only a few of the works depict wholly realistic turtles in their natural environments. Most of the paintings and sculptures feature bright colors and stylized surroundings. The sculpture "Stream of Unconsciousness" shows baby turtles on their trek into the sea, but in the artist's whimsical style.
The exhibit will be showcased in the URI Library until March 1. It is free and open to the public.
Exhibit in library displays many sides of turtles
February 02, 2007

Duke University Geologist's Book Assails Unrealistic Mathematical Models

newswire.ascribe.org
DURHAM, N.C., Jan. 25 (AScribe Newswire) -- Using equations to forecast the specific behavior of complex natural processes such as beach erosion and long-term nuclear waste storage creates a false sense of security, according to a new book by a retired Duke University geologist and his geologist daughter.
In a preface to "Useless Arithmetic: Why Environmental Scientists Can't Predict the Future," Orrin Pilkey and Linda Pilkey-Jarvis write that relying on such mathematical models has "done tangible damage to our society in many ways."
Among their examples, the pair charge that faulty mathematical models contributed to the collapse of a prime North American fishery. They say such models also are predicting unreachable margins of safety at a planned national U.S. high-level radioactive waste repository and have given coastal communities overly optimistic expectations about the endurance of beach nourishment projects.
"We make this point again and again: if your basic assumptions are wrong, it doesn't matter what the math does," said Pilkey, a retired professor at Duke's Nicholas School of the Environment and Earth Sciences.
"Since scientists now have computers on their desks that can do all kinds of sophisticated calculations, they have been saying 'give us enough money and we'll come up with a good model,'" he added. "And they have failed miserably. We scientists have to hang our heads in shame. We should have, long ago, admitted our weaknesses."
The authors focus their criticisms on quantitative mathematical models, which they define as those attempting to make specific predictions about natural outcomes by answering the questions "when," "where" and "how much."
In the case of the now-collapsed Grand Banks cod fishery, the authors argue that Canadian scientists used unrealistic quantitative models of total allowable catch to determine harvesting levels. "According to these models, the Grand Banks should still be full of fish," they write.
In its assessments of the unfinished Yucca Mountain high-level nuclear waste site in Nevada, the U.S. government has used a "pyramid" of hundreds of quantitative mathematical models to predict the repository's long-term behavior, according to the authors. Those flawed models, they write, predict a questionable 10,000 years of certainty that natural processes will not cause the repository to leak radiation.
"Of all the examples of quantitative models that I looked at, the worst is the U.S. Army Corps of Engineers' modeling of the behavior of beaches," said Pilkey, who has also assailed those models in previous books on coastal development. "There is no truth in those models at all."
State and local governments use Corps models to guide engineering projects to "nourish" eroded beaches with imported sand. To receive federal funding, the government agencies must predict in advance the life span of the beach nourishment projects in order to ensure that the benefits outweigh the costs, and project supporters typically use modeling to make such predictions, the geologists write. But, they added, some of those beaches have been replenished more than 20 times since the early 1960s.
"Agencies that depend upon project approvals for their very survival (such as the U.S. Army Corps of Engineers) can and frequently do find ways to adjust models to come up with correct answers that will ensure project funding," the book adds.
While condemning quantitative modeling, the book is more supportive of qualitative models that predict only direction and magnitudes of natural phenomena while accepting the possibility of being "imprecise or wrong to some degree." As examples of good modeling, the authors cite hurricane-tracking forecasts and global climate models.
Pilkey, the James B. Duke Professor Emeritus of Geology at the Nicholas School, began Duke's Program for the Study of Developed Shorelines, which is now a joint program with Western Carolina University. An expert in the geology of deep ocean plains, he has also written numerous books on how ocean forces and human development jointly affect beaches.
Pilkey-Jarvis is a geologist and expert on oil spills for the state of Washington's ecology department.
BOOK: "Useless Arithmetic: Why Environmental Scientists Can't Predict the Future," Orrin Pilkey and Linda Pilkey-Jarvis, Columbia University Press, 2007

- - - -

CONTACT: Monte Basgall, Duke University Office of News & Communications, 919-681-8057, monte.basgall@duke.edu
Duke University Geologist's Book Assails Unrealistic Mathematical Models

February 02, 2007

Mathematics in Ancient Egypt

weekly.ahram.org.eg
Did the Ancient Egyptians possess an ingenious skill for calculation? Assem Deif works out an ancient problem
The Greeks developed mathematics as a deductive science that reached its climax with Euclid of Alexandria in his masterpiece The Elements. Before that, during the ancient Egyptian era, mathematics was an inductive discipline of a utilitarian nature used to perform practical tasks such as flood control or land measurement using rope. It has been suggested that mathematics then amounted to no more than the two-times table and the ability to find two-thirds of any number. The whole structure of Egyptian mathematics was said to be based on these two simple rules, and indeed no evidence exists of a textual geometry with constructions and proofs.
Yet, looking at the Egyptians' stunning monuments, as well as a civilisation that spanned three millennia, one might expect to find a similar element of grandeur in their sciences -- especially in mathematics and astronomy. How did they configure the manpower and materials needed to build more than 90 pyramids? It is obvious that to calculate the vast amount of computations they needed, the ancient Egyptians reached a fairly advanced mathematical knowledge.
Several eminent Greek mathematicians -- Pythagoras, Thales and Archimedes, to name just a few -- worked in Egypt, and it is likely that Egyptian mathematics was absorbed into the body of Greek mathematics. The Giza pyramids offer definitive evidence of the ancient accuracy of measuring. Built in the middle of the third millennium BC, shortly after the first known evidence of Egyptian writing, they predate by 600 years any early mathematical tools. The Great Pyramid of Khufu was built of 2,300,000 limestone blocks each averaging 2.5 tons. Simple calculations reveal that, since it took 20 years to complete, and assuming that work lasted eight hours per day, it was possible to fit 2,300,000/20 x 365 x 8 x 60 = 0.7 blocks per minute. In other words it took about 10 minutes to fit seven such huge blocks neatly into place at such an elevation. This does not account for the time taken to construct or demolish the ramp using to pull up the stones.
One engineer reckons that such a ramp would require 18,000,000 m of material -- seven times the amount used for the pyramid itself, and necessitating a work force of 240,000 during Khufu's reign and more than 300,000 to dismantle it for at least eight years afterwards. Neither does it account for the time taken to position the nine blocks each weighing 50 tons for the inside of the royal chambers, or the time to clad the monument with casing stones. Astonishingly, an experiment by Japanese researchers 15 years ago to build a pyramid using new technology was abandoned after six months when their calculations showed it would take more than 1,000 years to complete their task.
No two Egyptologists agree on the exact dimensions of the Great Pyramid, yet all accept that the sides agree in length within 0.01 per cent, and that the right angles are equally accurate. The pyramid's 350-foot-long descending passage is so straight that it deviates from a central axis by less than a quarter of an inch from side to side and only one tenth of an inch up and down. This compares only with the best laser-controlled drilling of today.
Another perplexing feature of the Great Pyramid are the four so-called "air shafts", two in the King's Chamber and two in the Queen's. In each chamber, one is directed precisely to the North while the other is set precisely to the South. Whether these shafts were intended for ventilation or to serve a religious purpose is a mystery. The alignment of the shafts was difficult to attain, especially since they were made during construction. The builders appear to have selected a "target star", visible to the naked eye and rising high enough so as not to be disturbed by the earth's atmosphere. This would be viewed through the shaft during each phase of construction. The pyramid builders were able to insert these almost perfectly straight shafts directly North and South hundreds of feet from inside the pyramid and with almost a laser-beam precision. The shafts' alignments to the star's culmination points are so precise that they point exactly to the three stars of Orion's Belt, which the Egyptians relied heavily on in their astronomical observations.
The casing stones covering the monument are also so perfectly shaped that the mortar-filled joint is just 1/15th of an inch. Egyptologist Flinders Petrie compared such phenomenal precision with that of the finest optician, saying it was beyond the capabilities of modern technology. Again, these stones show no tool marksn and the corners are not even slightly chipped.
Monuments elsewhere show equal feats of engineering. The Karnak temple complex has 134 carved granite pillars, each 22m in height and 3.5m in diameter. Some obelisks are 42m high and weigh 1,100 tons. How did these early engineers raise them upright?
They had no electronic calculators, only ropes and rods. Yet they knew accurate values for both pie and sigma . They were aware of Pythagoras's theorem -- and not just as having sides with the ratio 3:4:5. Pythagoras himself called it the "Sacred Triangle". In our view, he might have given this name not only to the triangle, but also to the Great Pyramid with its dimensions 220c, 280c and 356c. History records that Pythagoras announced his theorem as he departed from Egypt in 600 BC after living there for 22 years.
The Golden Ratio, also called Divine Proportion, is what artists reckon to be the ratio controlling the dimensions of any beautiful figure and which applies to monuments from the Parthenon and the domes of Persia, to the art of the Renaissance.
It is beyond doubt that the Great Pyramid is a testament to the builders' remarkable ability precisely to measure directions, angles and lengths on the earth's surface. The pyramid exhibits such a high degree of precision in construction and orientation that it is little wonder ill- founded legends have grown up around it. It is said to be the most accurately aligned structure in existence, facing true North with only 3/ 60th of a degree of error (the misalignment in the telescope's sensor axis of the Paris observatory is 7min of arc, or twice the pyramid's error, while the Meridian Building at Greenwich Observatory in London has an inclination of 9min). Moreover, the pyramid's site was selected so as to allow for astronomical observations. It was determined as a site that would be suitable for a building with 61/2 million tons of stone, whose height was 147m and base area 53000 m . So, whereas Egyptologists adopt the view that the ancient Egyptians built the Great Pyramid as a tomb for Khufu, others suggest that their intention was to build a geodesic monument that would demonstrate their knowledge of the earth's shape and size, or perhaps an astronomical observatory.
In any event, what knowledge did the ancient Egyptians possess in order to construct such colossal structure and with such outstanding precision? We are forced to conclude that the pyramid builders were capable of making precise geodesic and astronomical calculations.
Another reason for believing in these skills is their accurate calendar. The Egyptians could not have devised a calendar with such remarkable sophistication unless they were well-versed in astronomy, a science we cannot dissociate from either mathematics or religion in ancient Egypt. A nation capable of mastering astronomy must have possessed advanced mathematical know-how.
One of the most astounding pieces of Egyptian architecture is Abu Simbel. A marvel of engineering, the temple construction depends on precise astronomical calculations. Thanks to the orientation of the temple, twice a year on 22 February and 22 October -- the anniversaries of Rameses's birthday and his coronation day -- the statues of the gods Amun-Ra and Re-Horakhte and of the pharaoh in the inner temple are struck at dawn by a shaft of sunlight. This spectacle continued for more than 3,200 years until the 1960s when the temple was dismantled and relocated to make way for the High Dam. After that the illumination shifted by one day.
Two major mathematical documents have survived; the Rhind and the Moscow papyri. Also still in existence are the Egyptian Mathematical Leather Roll, a table of 26 decompositions of unit fractions, a well as the Berlin Papyrus which contains two problems on simultaneous equations, one of second degree, and the Reisner Papyrus demonstrating the practical application of mathematics in construction and commerce. It is from the first two documents that we have obtained most of our information on Egyptian mathematics.
The papyrus, purchased by A Henry Rhind in Luxor in 1858 was written about 1650 BC by the scribe Ahmes, who stated that he was copying a document 200 years older. The papyrus contains multiplication tables, along with 87 problems involving a variety of mathematical processes.
The Moscow Papyrus which dates from 1890 BC contains some 25 problems. Number 14 shows a figure resembling an isosceles trapezoid: the calculations associated with it indicate that it is the frustum of a square pyramid. The formula was not written on the papyrus, but it was evidently known to the Egyptians.
"Squaring the circle" is the most fascinating problem that the Egyptians tackled, and, by far, the most famous and intricate mathematical problem ever posed in antiquity. By using simple geometrical instruments such as a compass and ruler, it seeks to find a square of an area equal to that of a given circle. Only after three and a half millennia (in the late 19th century) was it shown that such a square could not be constructed. The reason is that it is not an algebraic number. The Egyptians were the first to pose this problem, by stating in problem number 50 of the Rhind Papyrus, that a circle of nine units in diameter is equal in area to a square with a side of eight units.
By far the most intriguing is problem 14 of the Moscow Papyrus. It asks for the volume of a truncated pyramid (frustum), stating: "Given a truncated pyramid of height 6, base 4, and top 2".
An important find at Saqqara was a Third-Dynasty limestone ostracon dating from about 2700 BC. Egyptologists believe this architect's plan of a curved section of a roof is an example of the use of rectangular coordinates. For horizontal coordinates spaced one cubit apart, the vertical height is given for points which define a curve. The curve in the sketch exactly matches the curve of a nearby temple roof. This appears to be the earliest use of rectangular coordinates, and is another example of sophisticated mathematical concepts found in practical applications outside of the surviving mathematical papyri.
Instead of numbers, the Egyptians used symbols which started at one and went up to a million. Number one was a papyrus leaf, 10 a tied leaf, 100 a piece of rope, 1000 a lotus flower, 10,000 a snake, 100,000 a tadpole and 1,000,000 a scribe with raised arms. One major disadvantage was its lack of the zero, but neither the Babylonians nor the Greeks had zero either, although the Hindus, Greeks and Mayans knew of it as a symbol. It was the Arabs near the end of the first millennium AD who introduced it in numbers and later used it to solve algebraic equations.
Hieroglyphic numerals did not remain constant, but changed continuously over time. A New Kingdom script differs from the Middle Kingdom, and so on. When hieroglyphs were carved on stone, there was no need to develop forms which were quick to write. However, once the Egyptians began to use dried papyrus reed as paper and its tip as a pen, they needed to develop a more rapid means of writing. This prompted the development of fast hieratic writing. Later, a system of hieratic numerals was introduced, allowing numbers to be written in a more compact form: the number 9999 had just four hieratic symbols instead of 36 hieroglyphs. Examples of hieratic writing are the Rhind and Moscow papyri; meanwhile the carving on stone remained in hieroglyphs.
Today's scientists are searching desperately to fill the many blanks in the history of the Egyptian civilisation. There are very few sources on Egyptian mathematics, but these still give plenty of information about the level of mathematics. In fact, what current knowledge the West considers as originating mostly -- if not all -- from Babylon or Greece is beyond any doubt inherited from the ancient Egyptians. Such early historians as Solon, Hecataeus of Melitus, Herodotus, Diodorus and Strabo agreed that all the prominent Greek scientists, without a single exception, visited Egypt. Some historians, physicians and even philosophers stayed for more than 10 years in Waset, or Thebes. Further, All historians agree that one science in which the Greeks borrowed heavily from the Egyptians was medicine, so it seems plausible that they also borrowed in the other sciences.
If this is the case, then it would be legitimate to ask why most of the ancient written heritage was lost but the Greek was preserved to reach European Renaissance in the form we know today. The answer probably lies in that sciences in the Hellenistic era were written in Greek, a language that was understood and thus translated into Latin or Arabic. Hieroglyphs and hieratic, unidentified and written on fragile papyrus or parchment, did not survive. Thus it was left to the Greeks to reap the acclaim.

* The writer is professor of Mathematics at Cairo University.
Mathematics in Ancient Egypt

February 02, 2007

Noted peace researcher Rapoport dies at 95

www.mlive.com
Ex-U-M professor helped organize teach-in against Vietnam War
BY DAVE GERSHMAN
News Staff Reporter
Wednesday, January 24, 2007
As a professor at the University of Michigan in the 1960s, Anatol Rapoport was an early critic of the Vietnam War, and one of the faculty members involved with the nation's first teach-in, held in Ann Arbor.
Rapoport, who moved his family to Toronto in 1970, died Saturday at the age of 95. But his passion is still felt in Ann Arbor.
Long after the conflict in Southeast Asia had ended, he was still motivated by the same spark. "He kept up his opposition to war throughout his life,'' said his son, Anthony.
Rapoport was a professor of mathematical biology in the department of psychiatry at U-M. After leaving Ann Arbor, Rapoport taught at the University of Toronto, where he became the school's first professor of peace and conflict studies. In academia, he was highly-regarded for his research in the mathematical study of human decisions, and considered a leading peace researcher.
While at U-M in the mid-1950s, Rapoport was a founding member of the U-M Mental Health Research Institute.
Rapoport volunteered for military service after the attack on Pearl Harbor. He served as a supply officer in the U.S. Army Air Forces in Alaska and India during World War II. But during the years that followed, his views on war evolved as technology and the development of nuclear weapons made war more deadly and impersonal, said Anthony Rapoport.
The senior Rapoport was fond of saying "you don't have to hate anybody to kill everybody,'' his son recalled.
While at U-M in 1965, Rapoport was one of the faculty members who organized and participated in the first campus teach-in as an intellectual protest against the war. Rather than attend regular classes, students participated in anti-war seminars and rallies during the teach-in. The idea resonated on other campuses and similar events were spawned across the country.
Rapoport was a frequent speaker at rallies against the war. In April 1967, for instance, he was quoted in an Ann Arbor News article about a rally of 300 people outside city hall. "By undertaking the war against Vietnam, the United States has undertaken a war against humanity,'' Rapoport told the crowd that day. "This war we shall not win.''
One of his colleagues at U-M, J. David Singer, a professor emeritus of political science, called Rapoport an important catalyst for peace activists on campus and a brilliant speaker. "He was an extremely responsible, honest guy,'' said Singer. "He did not fiddle with the truth.''
The two professors were active in what was called the Center for Research on Conflict Resolution, founded to involve scientific evidence with national policy. "We were not just a bunch of peaceniks,'' said Singer. "We were a bunch of peaceniks who were very critical of U.S. policy, and the criticism would range from moderate on my part, to extreme on his part.''
Born in Russia, Rapoport moved with his parents to Chicago in 1922. He studied in Vienna to become a concert pianist in the 1930s before returning to his adopted hometown to follow a different pursuit and study mathematics at the University of Chicago.
Rapoport is survived by his wife, Gwen, and his three children, Anya, Alexander, and Anthony, all living in the Toronto area.

Dave Gershman can be reached at 734-994-6818 or dgershman@annarbornews.com.
Noted peace researcher Rapoport dies at 95

February 02, 2007

Strange but True: Turning a Wobbly Table Will Make It Steady

www.sciam.com
For every table—turn, turn, turn... there is a proof By JR Minkel
It's a problem as old as civilization: the wobbly table. You may have thought your only recourse against this scourge is a hastily folded cocktail napkin stuffed under the offending leg. If so, take heart, because mathematicians have recently proved a more elegant solution. Just rotate the table.
The intuitive argument, which dates back at least to a 1973 Scientific American column by Martin Gardner, is straightforward. Consider a square table with four equally long legs. Any three of the legs must be able to rest on the floor simultaneously, as a tripod does. Assume the floor undulates smoothly and the fourth leg hovers above it.
Now imagine turning the table about its center while keeping the first three legs grounded, or balanced. Once the table has rotated by 90 degrees, the wobbly leg must lie below the floor. (If you do not see why, imagine pushing down equally on the wobbly leg and a neighboring leg until the neighbor sinks below the floor and the wobbly leg touches down.) And so, at some point along the wobbly leg's arc, it has to hit a spot on which it can rest. As simple as this argument may sound, however, proof was a long time coming.
The first serious mathematical inroad against table wobbling seems to have occurred in the late 1960s with Roger Fenn, a PhD student at the University of London. One day Fenn and his graduate adviser ended up at a coffee shop faced with—you guessed it—an unsteady table. "The table wouldn't stop wobbling and we fiddled it around until we got it to stop," recalls Fenn, who is now at the University of Sussex.
At his adviser's suggestion, Fenn wrote out a proof that for any smoothly curving floor that bulges upward like a hill, there is at least one way to position the table so that it is balanced and horizontal. But he did not reveal how exactly to find that sweet spot, and he quickly tabled the subject. "I didn't think people were going to take this very seriously," he admits. "You say to somebody you've met, 'Well I'm trying to put a table on the floor so it doesn't wobble'; they'll say, 'Oh yeah?'"
The season for proving the table turning hypothesis would not arrive for another 35 years. By then, the idea had become such a part of mathematical lore that two years ago mathematician Burkard Polster of Monash University in Australia included it in an article on neat math tricks for teachers. He promptly received a letter pointing out that the idea would not work if a floor possessed sheer cliffs, such as between tiles.
Polster rose to the challenge. "It's never been really pinpointed exactly what the ground should be like," he says. So he and some of his colleagues ran through the appropriate calculus and satisfied themselves that if a floor has no spots that slope by more than 35.26 degrees, then turning will indeed balance a square or rectangular table—although the table may not end up level. They detail the proof in a paper accepted for publication by the Mathematical Intelligencer. (In one of those odd cases of co-discovery, a retired CERN physicist named André Martin published a similar result within a few months of the Australians' version.) Polster's group even spells out a procedure for balancing the table [see video above]. First lift up the leg of the table diagonal from the wobbly leg. Make sure both legs are roughly equal distances off the ground and then begin rotating. "In practice," the researchers write, "it does not seem to matter how exactly you turn your table on the spot, as long as you turn roughly around the center of the table."
So, next time you feel a table start to tilt, put that napkin down and don't be shy about turning the tables on a wobbly dining experience. Rest assured, mathematics is on your side.

RELATED LINKS:
The proof by Polster and his colleagues
Martin's proof "Mathsnacks"
a column by Polster and Marty Ross for Vinculum magazine

Strange but True: Turning a Wobbly Table Will Make It Steady

February 02, 2007

Does evolution select for faster evolvers?

www.eurekalert.org
Horizontal gene transfer adds to complexity, speed of evolution
HOUSTON, Jan. 29, 2007 -- It's a mystery why the speed and complexity of evolution appear to increase with time. For example, the fossil record indicates that single-celled life first appeared about 3.5 billion years ago, and it then took about 2.5 billion more years for multi-cellular life to evolve. That leaves just a billion years or so for the evolution of the diverse menagerie of plants, mammals, insects, birds and other species that populate the earth.
New studies by Rice University scientists suggest a possible answer; the speed of evolution has increased over time because bacteria and viruses constantly exchange transposable chunks of DNA between species, thus making it possible for life forms to evolve faster than they would if they relied only on sexual selection or random genetic mutations.
"We have developed the first exact solution of a mathematical model of evolution that accounts for this cross-species genetic exchange," said Michael Deem, the John W. Cox Professor in Biochemical and Genetic Engineering and professor of physics and astronomy.
The research appears in the Jan. 29 issue of Physical Review Letters.
Past mathematical models of evolution have focused largely on how populations respond to point mutations – random changes in single nucleotides on the DNA chain, or genome. A few theories have focused on recombination – the process that occurs in sexual selection when the genetic sequences of parents are recombined. Horizontal gene transfer (HGT) is a cross-species form of genetic transfer. It occurs when the DNA from one species is introduced into another. The idea was ridiculed when first proposed more than 50 years ago, but the advent of drug-resistant bacteria and subsequent discoveries, including the identification of a specialized protein that bacteria use to swap genes, has led to wide acceptance in recent years.
"We know that the majority of the DNA in the genomes of some animal and plant species – including humans, mice, wheat and corn – came from HGT insertions," Deem said. "For example, we can trace the development of the adaptive immune system in humans and other jointed vertebrates to an HGT insertion about 400 million years ago."
The new mathematical model developed by Deem and visiting professor Jeong-Man Park attempts to find out how HGT changes the overall dynamics of evolution. In comparison to existing models that account for only point mutations or sexual recombination, Deem and Park's model shows how HGT increases the rate of evolution by propagating favorable mutations across populations.
Deem described the importance of horizontal gene transfer in the work in a January 2007 cover story in the Physics Today, showing how HGT compliments the modular nature of genetic information, making it feasible to swap whole sets of genetic code – like the genes that allow bacteria to defeat antibiotics.
"Life clearly evolved to store genetic information in a modular form, and to accept useful modules of genetic information from other species," Deem said.
###

The research is supported by the Defense Advanced Research Projects Agency.
Does evolution select for faster evolvers?
February 02, 2007

Mathematician turns chaos into crochet

http://abc.net.au
lorenzmanifold
This crocheted representation of a
mathematical equation may one day allow researchers to make
better weather predictions (Image:
University of Bristol)
Osinga and Krauskopf
Osinga and Krauskopf pose with
the Lorenz manifold (Image:
University of Bristol)
Monday, 29 January 2007
Anna Salleh
ABC Science Online
Crochet is helping researchers to better understand mathematical equations designed to make sense of chaotic weather patterns.
Dr Hinke Osinga, a mathematician from the University of Bristol, will discuss her work at the Australian and New Zealand Industrial and Applied Mathematics meeting in Fremantle this week.
Osinga is working on the Lorenz equations, which are used to model the difficult-to-predict system we know as the weather. In these equations, small changes in initial conditions have a big effect on the long-term behaviour of the system. This is the maths behind the idea that a butterfly flapping its wings in one part of the world affects the weather in another. What makes weather prediction difficult is being precise enough when defining these initial conditions.
Osinga and colleague Professor Bernd Krauskopf have been working on visualising the Lorenz equations, which is how Osinga ended up with a crochet model. Part of modelling the weather is predicting how air particles behave. And the researchers liken air particles in turbulent weather to leaves dropped upstream of a rock in a turbulent river.
It's difficult to predict where the leaves will flow in relation to the rock, says Osinga. The Lorenz equations simplify such a system to predict the path of these leaves. But the equations are limited because they are dynamic. You have to wait and see what happens over time to see what path the leaves take, says Osinga. She and Krauskopf decided to try and get a static picture of what happens in such a system.
They took a particular set of solutions to the equations that modelled, in the river analogy, the 'middle path' in which leaves head straight for the rock and stick to it. They modelled this on a computer and found it gave a unique complex curved shape, they called the 'Lorenz manifold', that centred on one point. "On the top part, the geometry is incredibly complex where you have a helical rotation going up and you have a spiralling rotation going in one of the opposite directions," Osinga says.
While staring at the Lorenz manifold on computer, Osinga had a brainwave. "I realised the way that we computed the surface naturally translated into crochet instructions," she says. "When I saw that, I just had to try. It was too good for words really that you could actually make one." Osinga, the daughter of a handicrafts teacher, spent 85 hours crocheting a 3D model that she says really put things in perspective.
For a start, she says the model gave her an idea of the size of chaotic systems in real life. And reducing a system of chaotic behaviour into a unique shape also gave Osinga a better understanding of the Lorenz equations themselves. "Here we have an instant image and it tells us quite a lot," she says.
She says the crocheted 3D model could tells us what kind of weather patterns the Lorenz equations are best at predicting. Apart from that, though, the crocheted Lorenz manifold is a fascinating thing in itself, says Osinga. "It has absolute artistic value. I get lots of comments from artists who've found out about this that are totally smitten by the shape," she says.
Mathematician turns chaos into crochet
February 02, 2007

The visual beauty of discrete geometry, The new mathematical film Mesh is a prizewinner

www.webwire.com
Heidelberg, 26 January 2007
The mathematical film Mesh, recently released by Springer, has already won numerous international prizes. Mesh is a groundbreaking 40-minute computer animation that explores the advancement of discrete geometry from the ancient Greeks to contemporary research topics.
At the Digital Media Festival in Melbourne, Australia in June 2005, an excerpt of Mesh was awarded best in the category of Corporate/Government/Training. Three months later, the clip Mesh: Bubble Excerpt was chosen for the "Best Scientific Video" award at Eurographics in Dublin, Ireland. At its North American debut in September 2005 at the New York International Independent Film and Video Festival, Mesh won the prize of "Best Animation." With continuing success, Mesh was awarded "Best Scientific Visualization" at the Red Stick International Animation Festival in April 2006 in Baton Rouge, Louisiana. Once again in Australia, Mesh won the "Best Experimental Film" at Scinema - International Festival of Science Film in August 2006 in Sydney.
With its synthesis of cutting-edge visualization, breathtaking artistry, storytelling and humor, Mesh presents complex ideas in a way that is palpable and relevant to even a novice audience. The result is an ideal teaching tool that entertains and captivates. Along the way, the viewer encounters applications ranging from crystals and computer graphics to wine barrels and soap bubbles.
Many of the topics in Mesh have never before been portrayed with computer graphics while other concepts had only been communicated through very laconic, clinical means. Creators Beau Janzen and Konrad Poltheir saw Mesh as an opportunity to expand the possibilities of mathematical visualization.
"Mesh provides a unique and unprecedented visualization of advanced differential geometric properties and constructions," says Polthier. "For example, nobody has ever seen this visually enlightening scientific explanation for the construction of bubbles before."
"Computer animation has already changed the way we make movies. It can generate visual effects that were previously unthought-of, and has even changed the kind of scripts that can be produced," says Janzen, "Now, we want to bring the same revolution to education."
Dr. Konrad Polthier is professor of mathematics at the Free University of Berlin, and scientist in charge of the application area "Visualization" at the German Research Foundation Center MATHEON. Having published over 40 research articles on a wide range of mathematical topics, serving as editor of book and video series, and acting as coordinator for the VisMath conferences, Polthier has become one of the pioneering scientists in mathematical visualization.
Beau Janzen has a BS in Graphic Design and a MS in Instructional Systems Design. He currently is a faculty member at the Art Institute of California, Los Angeles where he teaches mathematics and computer animation. Janzen has written, designed, and animated short educational videos for clients including NASA and General Motors. He has also worked on a wide range of projects raging from feature films to television commercials.

Beau Janzen, Konrad Polthier
MESH
Springer 2007
DVD (PAL) EUR 29.95, £23.00, $29.95, sFr 52.00,
ISBN: 978-3-540-28478-9
DVD (NTSC) EUR 29.95, £23.00, $29.95, sFr 52.00,
ISBN: 978-3-540-28484-0
The visual beauty of discrete geometry, The new mathematical film Mesh is a prizewinner