A Bimonthly Email Newsletter from the International Mathematical Union

Editor: Mireille Chaleyat-Maurel, University Paris Descartes, Paris, France

## Editorial

Next week I will attend a workshop on the mathematics of weather and climate prediction. It is a subject that I know very little about, but which intrigues me as one in which mathematics can perhaps contribute critically to a problem facing all humans. For example, the question of which features of the climate are predictable seems to me to have a deep mathematical component. In the present global financial crisis we see both the potential of mathematical modelling to help restabilize the world economy, and the possibility that complex financial instruments created by mathematicians may have been one element in precipitating the crisis itself.

Thus mathematics has the capacity to change the world. But it is not more responsible or moral to work on mathematical models of the heart than on, say, the Langlands programme. Leaving aside aesthetic reasons, to argue thus would deny the value for future applications of mathematics of the subject developing naturally according to its intrinsic structure. Yet the choice of what problems to work on is one of the most important that faces researchers, and the contribution that mathematics can make to society is a legitimate consideration in this choice.

John Ball

## News from IMU

1. Visa problems

At the General Assembly 2006 in Santiago de Compostela, Spain, the International Mathematical Union (IMU) adopted the following resolution:

"The General Assembly of the IMU continues to endorse the principle of universality expressed in the International Council for Science (ICSU) ARTICLE 5 of the STATUTES, as adopted by the 1998 General Assembly, and endorses the additional ICSU Statement on the Universality of Science (2004) (see http://www.icsu.org/Gestion/img/ICSU_DOC_DOWNLOAD/567_DD_FILE_Universality.pdf).

Notwithstanding heightened tensions, security concerns, etc., the General Assembly urges free exchange of scientific ideas and free circulation of scientists and mathematicians across international borders. The IMU opposes efforts by governments to restrict contacts, interactions, access and travel in the world mathematical community, particularly when such restrictions penalize individual mathematicians for the actions of governments."

see Resolution 10 at http://www.mathunion.org/Organization/GA/Resolutions/RESOL2006.pdf

ICSU has received a number of reports that some governments make it difficult, e.g., due to security clearance issues, for scientists to obtain visas in time to allow them to attend meetings. The attached letter from ICSU's Deputy Executive Director Carthage Smith is meant to alert scientists about this situation.

IMU asks all its adhering organization and all mathematical societies to inform its members of this issue and contact their governments in order improve this frustrating situation.

2. EC meeting in Fuzhou, China

IMU's Executive Committee will meet in Fuzhou, China, on April 17-19.

## Abel Prize 2009

The Norwegian Academy of Science and Letters has decided to award the Abel Prize for 2009 to

Mikhail Leonidovich Gromov

Institut des Hautes Études Scientifiques, Bures-sur-Yvette, France

for his revolutionary contributions to geometry.

The President of the Norwegian Academy of Science and Letters, Øyvind Østerud, announced the winner of Abel Prize at the Academy in Oslo on March 26. Mikhail L. Gromov will receive the Abel Prize from His Majesty King Harald at an award ceremony in Oslo, May 19. The Abel Prize recognizes contributions of extraordinary depth and influence to the mathematical sciences and has been awarded annually since 2003. It carries a cash award of NOK 6,000,000 (close to EUR 700,000, USD 950,000).

For more information about the laureate, his achievements and the Abel Prize, visit the Abel Prize website:

## 2011 ICPAM-CIMPA research schools

Research schools call for projects begins on March 1st, 2009. The deadline for a pre-proposal is June 15, 2009. The complete proposal is due October 1st, 2009.

For more information:

## IMU ON THE WEB: Mathematical Notation on the Web

The Mathematics Markup Language (MathML) activity of the World-Wide Web Consortim (W3C) grew out of the HTML-Math effort of 1994. Early work on MathML paralleled the development of the eXtensible Markup Language (XML), and the two influenced each other. MathML was in fact the first XML application: a fact not surprising to those who practice the "Queen of the Sciences". Mathematics uses a complex and highly evolved system of two-dimensional symbolic notations. Indeed in traditional typesetting mathematics was known as "penalty copy" because of the difficulty of the two-dimensional arrangements and the large range of characters.

These challenges have translated into electronic world of browsers, both for the two-dimensionality and the range of characters. Browsers have started to develop, either directly or via various "plug-ins", the ability to handle the two-dimensionality. The question of names for the large range of mathematical symbols needed has been largely solved as a part of the process which extended the Unicode standard to include symbols for other world languages. The remaining challenge is the availability of what are known as "glyphs", i.e. what the characters look like. Here it is must be admitted that the situation is less satisfactory. Even if one has access to the glyphs (and this is not always the case), it is rare that they match the font of the ordinary characters in the surrounding text. This tends, at the moment to lead to ugly but readable text on the web, as can be found in the abstracts of many journals, as viewed by some browsers under some configurations of fonts. It is the caveats in the last sentence that indicate the problem: the publisher can have no idea what set of glyphs will be chosen by the browser. However, the fact that we are discussing "ugly" rather than "unusable" illustrates the progress that has been made, and there is more work being done (under the auspices of STIX - http://www.aip.org/stixfonts/) to solve these problems.

As pointed out in an early draft of MathML (http://www.w3.org/TR/WD-math-980106/chapter1.html)

"The challenge in putting math on the Web is to capture both notation and content in such a way that documents can utilize the highly-evolved notational practices of print, and the potential for interconnectivity in electronic media. "

This challenge means that MathML essentially developed two languages: one for notation (Presentation MathML or MathML-P) and one for content (Content MathML or MathML-C). It is worth noting that neither is intended for direct human consumption: MathML-P will be written by editors and other software tools, and rendered by browsers or printing engines, and MathML-C is intended for direct production and consumption by software tools with a deep capability to manipulate the mathematical meaning thus encoded. Hence clarity and machine readability (parsing) take priority over conciseness. MathML compresses very well!

With that caveat, MathML-P will seem familiar in concept to LaTeX users. Perhaps the biggest difference is that a horizontal row is explicit in MathML-P, So LaTeX's a+b becomes a row of (the MathML encodings of) a, plus and b. The reader is referred to http://www.w3.org/TR/MathML/chapter2.html for more detail and examples. MathML-P differs from LaTeX, though, in having several operators that would render as white space on a printed page, such as ⁢ or ⁡, thus enabling a MathML-to-speech renderer (they do exist, and seem to be remarkably effective) to distinguish "f of x" from "f times x", even though both would print as "f x" (but with differing spacing, again implied by the 'invisible' symbols).

We will come back to MathML-C in a later article.

Olga Caprotti, James Davenport

Members of the IMU Committee on Electronic Information and Communication