Sabir Medgidovich Gusein-Zade

How time passes: our good friend and colleague Sabir Gusein-Zade has just turned 60, and we warmly congratulate him on his anniversary. Sabir, besides being a world renowned mathematician, is, among other things, one of the three Editors-in-Chief of MMJ, is a full professor at MSU and at the IUM, a member of the Board of the Moscow Mathematical Society.

Sabir's university education and professional life is strongly linked to Moscow State University: having received a gold medal at the International Mathematical Olympiad, he entered MSU as an undergraduate in 1966, there he obtained his Master's degree in 1971, his PhD in 1975 and his Doc.Sc. degree in 1992. After three years of graduate studies (1971–1974), he was hired as a junior researcher by the MSU Department of Geography, and went through all the research positions (senior researcher, leading researcher) at that department.

In 1996 he returned to his alma mater, mekhmat, as a full professor at S.P. Novikov's Topology and Geometry Chair.

First steps as a researcher Gusein-Zade made with the help of E.B. Dynkin. He solved Dynkin's problem of a fastidious bride, the result much appreciated by the broad mathematical community. His student years passed under the influence of S.P. Novikov. It is under his guidance that Sabir wrote a very important paper on cobordism of manifolds with a circle action. He continued to work with Novikov and at the same time gradually fell under the influence of Vladimir Arnold, becoming one of the best and favorite ones in the galaxy of Arnold's brilliant students. His Doc.Sc. thesis is in applied statistics, where he also marked important results.

It is from Arnold that Sabir inherited a life-long interest in singularity theory, combined with a wide range of other mathematical interests, a strong penchant for effectual applications of his research to real life situations, and a strong feeling for the beauty of mathematics.

Perhaps Sabir's most famous work is the book Singularity Theory of Differentiable Mappings written jointly with V.I. Arnold and A.N. Varchenko. First published in 1982, it immediately became a classic, and has remained the main reference in the field over the years, as witnessed by the fact that a new print run was produced by MCCME Publishers only last year.

After the publication of that book Gusein-Zade is known as one of the leading experts in the topology of singularities of analytic functions. While working on that book and later on, he obtained numerous results---now considered classical---in the subject: on monodromy and intersection matrices of complex singularities, on the Morsification of real singularities, on invariants of covector fields on singular manifolds.

Besides his work in fundamental mathematics (over 50 publications in peer-reviewed journals), Sabir has over 60 papers in leading journals in applied mathematics. His first articles in that field date back to the period when he was a junior researcher at the Department of Geography at MSU and are related to geographic subject matter. However, in a good deal of his later papers, the underlying mathematics is so deep and general, that this work can be useful in several practical fields at the same time, e.g. archeology, cancer research, sociology, etc. In applied mathematics, Sabir's most renowned result is the creation of a now famous algorithm for constructing continuous cartograms.

An interesting characteristic of Gusein-Zade's research is his recurring interest in several beautiful mathematical objects, to which he keeps returning time and time again, always contributing something new and original. Among them are Poincare series, Grothendieck rings, zeta functions, monodromy, the Alexander polynomial, Newtom diagrams, and, of course, isolated singularities.

Sabir Gusein-Zade is a brilliant lecturer and an excellent teacher; he regards his teaching duties not as a necessary yet unpleasant task, but as an occasion to share his vast mathematical knowledge with future mathematicians. For over ten years now, he holds a full professor position at the IUM, and has inspired many talented students to become working mathematicians.

Sabir's pedagogical interests are also very broad: he has written a popular science booklet aimed at a wide audience, “A Fastidious Bride”, about the stoppage time in random games. The booklet is related to Sabir's own serious research on probabilistic game theory mentioned above, another bright color in the wide spectrum of his research interests.

On the human side, Sabir is an excellent family man, father of two, a very responsible, efficient, and exacting person in his social and administrative duties. Sabir keeps the tradition going back to Arnold and Kolmogorov and symbolized by the proverb Mens sana in corpore sano. One of his coldest winter swims (at −27 Celsius) Arnold had together with Sabir. Sabir also is a very serious mountain hiker.

We wish Sabir continuing good health, new beautiful theorems in his favorite topics and in new ones, new brilliant pupils, continued success in his work at the head of MMJ and in all his enterprises.

S. B. Artemov, A. A. Belavin, V. M. Buchstaber, A. I. Esterov, B. L. Feigin, V. A. Ginzburg, E. A. Gorsky, Yu. S. Ilyashenko, A. A. Kirillov, A. G. Khovanskii, S. K. Lando, G. A. Margulis, Yu. A. Neretin, S. P. Novikov, S. B. Shlosman, A. B. Sossinsky, M. A. Tsfasman, A. N. Varchenko, V. A. Vassiliev, S. G. Vlăduţ