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MY UNFORGETTABLE EARLY YEARS at the INSTITUTE Enstitüde Unutulmaz Erken Yıllarım
MY UNFORGETTABLE EARLY YEARS AT THE INSTITUTE Enstitüde Unutulmaz Erken Yıllarım Dinakar Ramakrishnan `And what was it like,’ I asked him, `meeting Eliot?’ `When he looked at you,’ he said, `it was like standing on a quay, watching the prow of the Queen Mary come towards you, very slowly.’ – from `Stern’ by Seamus Heaney in memory of Ted Hughes, about the time he met T.S.Eliot It was a fortunate stroke of serendipity for me to have been at the Institute for Advanced Study in Princeton, twice during the nineteen eighties, first as a Post-doctoral member in 1982-83, and later as a Sloan Fellow in the Fall of 1986. I had the privilege of getting to know Robert Langlands at that time, and, needless to say, he has had a larger than life influence on me. It wasn’t like two ships passing in the night, but more like a rowboat feeling the waves of an oncoming ship. Langlands and I did not have many conversations, but each time we did, he would make a Zen like remark which took me a long time, at times months (or even years), to comprehend. Once or twice it even looked like he was commenting not on the question I posed, but on a tangential one; however, after much reflection, it became apparent that what he had said had an interesting bearing on what I had been wondering about, and it always provided a new take, at least to me, on the matter. Most importantly, to a beginner in the field like I was then, he was generous to a fault, always willing, whenever asked, to explain the subtle aspects of his own work. -
A Tour Through Mirzakhani's Work on Moduli Spaces of Riemann Surfaces
BULLETIN (New Series) OF THE AMERICAN MATHEMATICAL SOCIETY Volume 57, Number 3, July 2020, Pages 359–408 https://doi.org/10.1090/bull/1687 Article electronically published on February 3, 2020 A TOUR THROUGH MIRZAKHANI’S WORK ON MODULI SPACES OF RIEMANN SURFACES ALEX WRIGHT Abstract. We survey Mirzakhani’s work relating to Riemann surfaces, which spans about 20 papers. We target the discussion at a broad audience of non- experts. Contents 1. Introduction 359 2. Preliminaries on Teichm¨uller theory 361 3. The volume of M1,1 366 4. Integrating geometric functions over moduli space 367 5. Generalizing McShane’s identity 369 6. Computation of volumes using McShane identities 370 7. Computation of volumes using symplectic reduction 371 8. Witten’s conjecture 374 9. Counting simple closed geodesics 376 10. Random surfaces of large genus 379 11. Preliminaries on dynamics on moduli spaces 382 12. Earthquake flow 386 13. Horocyclic measures 389 14. Counting with respect to the Teichm¨uller metric 391 15. From orbits of curves to orbits in Teichm¨uller space 393 16. SL(2, R)-invariant measures and orbit closures 395 17. Classification of SL(2, R)-orbit closures 398 18. Effective counting of simple closed curves 400 19. Random walks on the mapping class group 401 Acknowledgments 402 About the author 402 References 403 1. Introduction This survey aims to be a tour through Maryam Mirzakhani’s remarkable work on Riemann surfaces, dynamics, and geometry. The star characters, all across Received by the editors May 12, 2019. 2010 Mathematics Subject Classification. Primary 32G15. c 2020 American Mathematical Society 359 License or copyright restrictions may apply to redistribution; see https://www.ams.org/journal-terms-of-use 360 ALEX WRIGHT 2 3117 4 5 12 14 16 18 19 9106 13 15 17 8 Figure 1.1. -
On the Uniqueness of Gibbs States in the Pirogov-Sinai Theory?
Commun. Math. Phys. 189, 311 – 321 (1997) Communications in Mathematical Physics c Springer-Verlag 1997 On the Uniqueness of Gibbs States in the Pirogov-Sinai Theory? J.L. Lebowitz1, A.E. Mazel2 1 Department of Mathematics and Physics, Rutgers University, New Brunswick, NJ 08903, USA 2 International Institute of Earthquake Prediction Theory and Mathematical Geophysics, Russian Academy of Sciences, Moscow 113556, Russia Received: 4 June 1996 / Accepted: 30 October 1996 Dedicated to the memory of Roland Dobrushin Abstract: We prove that, for low-temperature systems considered in the Pirogov-Sinai theory, uniqueness in the class of translation-periodic Gibbs states implies global unique- ness, i.e. the absence of any non-periodic Gibbs state. The approach to this infinite volume state is exponentially fast. 1. Introduction The problem of uniqueness of Gibbs states was one of R.L.Dobrushin’s favorite subjects in which he obtained many classical results. In particular when two or more translati- on-periodic states coexist, it is natural to ask whether there might also exist other, non translation-periodic, Gibbs states, which approach asymptotically, in different spatial directions, the translation periodic ones. The affirmative answer to this question was given by R.L.Dobrushin with his famous construction of such states for the Ising model, using boundary conditions, in three and higher dimensions [D]. Here we consider the opposite± situation: we will prove that in the regions of the low-temperature phase diagram where there is a unique translation-periodic Gibbs state one actually has global uniqueness of the limit Gibbs state. Moreover we show that, uniformly in boundary conditions, the finite volume probability of any local event tends to its infinite volume limit value exponentially fast in the diameter of the domain. -
2010 Table of Contents Newsletter Sponsors
OKLAHOMA/ARKANSAS SECTION Volume 31, February 2010 Table of Contents Newsletter Sponsors................................................................................ 1 Section Governance ................................................................................ 6 Distinguished College/University Teacher of 2009! .............................. 7 Campus News and Notes ........................................................................ 8 Northeastern State University ............................................................. 8 Oklahoma State University ................................................................. 9 Southern Nazarene University ............................................................ 9 The University of Tulsa .................................................................... 10 Southwestern Oklahoma State University ........................................ 10 Cameron University .......................................................................... 10 Henderson State University .............................................................. 11 University of Arkansas at Monticello ............................................... 13 University of Central Oklahoma ....................................................... 14 Minutes for the 2009 Business Meeting ............................................... 15 Preliminary Announcement .................................................................. 18 The Oklahoma-Arkansas Section NExT ............................................... 21 The 2nd Annual -
Symmetric Products of Surfaces; a Unifying Theme for Topology
Symmetric products of surfaces; a unifying theme for topology and physics Pavle Blagojevi´c Mathematics Institute SANU, Belgrade Vladimir Gruji´c Faculty of Mathematics, Belgrade Rade Zivaljevi´cˇ Mathematics Institute SANU, Belgrade Abstract This is a review paper about symmetric products of spaces SP n(X) := n X /Sn. We focus our attention on the case of 2-manifolds X and make a journey through selected topics of algebraic topology, algebraic geometry, mathematical physics, theoretical mechanics etc. where these objects play an important role, demonstrating along the way the fundamental unity of diverse fields of physics and mathematics. 1 Introduction In recent years we have all witnessed a remarkable and extremely stimulating exchange of deep and sophisticated ideas between Geometry and Physics and in particular between quantum physics and topology. The student or a young scientist in one of these fields is often urged to master elements of the other field as quickly as possible, and to develop basic skills and intuition necessary for understanding the contemporary research in both disciplines. The topology and geometry of manifolds plays a central role in mathematics and likewise in physics. The understanding of duality phenomena for manifolds, mastering the calculus of characteristic classes, as well as understanding the role of fundamental invariants like the signature or Euler characteristic are just examples of what is on the beginning of the growing list of prerequisites for a student in these areas. arXiv:math/0408417v1 [math.AT] 30 Aug 2004 A graduate student of mathematics alone is often in position to take many spe- cialized courses covering different aspects of manifold theory and related areas before an unified picture emerges and she or he reaches the necessary level of maturity. -
SENATE—Wednesday, July 26, 2000
July 26, 2000 CONGRESSIONAL RECORD—SENATE 16283 SENATE—Wednesday, July 26, 2000 The Senate met at 9:31 a.m. and was Again, if cloture is invoked on the mo- to be offered, the time for the debate, called to order by the President pro tion, postcloture debate will begin im- and some tangential but very impor- tempore [Mr. THURMOND]. mediately. tant issues such as the consideration of As a reminder, on Thursday the appointments of Federal district court PRAYER morning hour has been set aside for judges across America to fill vacancies. The Chaplain, Dr. Lloyd John those Senators who wish to make their These judgeships have been a source of Ogilvie, offered the following prayer: final statements in remembrance of great controversy in recent times be- Almighty God, take charge of the the life of our former friend and col- cause there is a clear difference of control centers of our brains. Think league, Senator Paul Coverdell. At the opinion between Democrats and Repub- Your thoughts through us and send to expiration of that time, a vote on the licans about how many judges should our nervous systems the pure signals of motion to proceed to the energy and be appointed this year. Your peace, power, and patience. Give water appropriations bill will occur. Of course, the Republicans in control us minds responsive to Your guidance. I thank my colleagues for their at- of the Senate are hopeful that their Take charge of our tongues so that tention. I yield the floor. I suggest the candidate for President will prevail in we may speak truth with clarity, with- absence of a quorum. -
Riemann Surfaces
RIEMANN SURFACES AARON LANDESMAN CONTENTS 1. Introduction 2 2. Maps of Riemann Surfaces 4 2.1. Defining the maps 4 2.2. The multiplicity of a map 4 2.3. Ramification Loci of maps 6 2.4. Applications 6 3. Properness 9 3.1. Definition of properness 9 3.2. Basic properties of proper morphisms 9 3.3. Constancy of degree of a map 10 4. Examples of Proper Maps of Riemann Surfaces 13 5. Riemann-Hurwitz 15 5.1. Statement of Riemann-Hurwitz 15 5.2. Applications 15 6. Automorphisms of Riemann Surfaces of genus ≥ 2 18 6.1. Statement of the bound 18 6.2. Proving the bound 18 6.3. We rule out g(Y) > 1 20 6.4. We rule out g(Y) = 1 20 6.5. We rule out g(Y) = 0, n ≥ 5 20 6.6. We rule out g(Y) = 0, n = 4 20 6.7. We rule out g(C0) = 0, n = 3 20 6.8. 21 7. Automorphisms in low genus 0 and 1 22 7.1. Genus 0 22 7.2. Genus 1 22 7.3. Example in Genus 3 23 Appendix A. Proof of Riemann Hurwitz 25 Appendix B. Quotients of Riemann surfaces by automorphisms 29 References 31 1 2 AARON LANDESMAN 1. INTRODUCTION In this course, we’ll discuss the theory of Riemann surfaces. Rie- mann surfaces are a beautiful breeding ground for ideas from many areas of math. In this way they connect seemingly disjoint fields, and also allow one to use tools from different areas of math to study them. -
“To Be a Good Mathematician, You Need Inner Voice” ”Огонёкъ” Met with Yakov Sinai, One of the World’S Most Renowned Mathematicians
“To be a good mathematician, you need inner voice” ”ОгонёкЪ” met with Yakov Sinai, one of the world’s most renowned mathematicians. As the new year begins, Russia intensifies the preparations for the International Congress of Mathematicians (ICM 2022), the main mathematical event of the near future. 1966 was the last time we welcomed the crème de la crème of mathematics in Moscow. “Огонёк” met with Yakov Sinai, one of the world’s top mathematicians who spoke at ICM more than once, and found out what he thinks about order and chaos in the modern world.1 Committed to science. Yakov Sinai's close-up. One of the most eminent mathematicians of our time, Yakov Sinai has spent most of his life studying order and chaos, a research endeavor at the junction of probability theory, dynamical systems theory, and mathematical physics. Born into a family of Moscow scientists on September 21, 1935, Yakov Sinai graduated from the department of Mechanics and Mathematics (‘Mekhmat’) of Moscow State University in 1957. Andrey Kolmogorov’s most famous student, Sinai contributed to a wealth of mathematical discoveries that bear his and his teacher’s names, such as Kolmogorov-Sinai entropy, Sinai’s billiards, Sinai’s random walk, and more. From 1998 to 2002, he chaired the Fields Committee which awards one of the world’s most prestigious medals every four years. Yakov Sinai is a winner of nearly all coveted mathematical distinctions: the Abel Prize (an equivalent of the Nobel Prize for mathematicians), the Kolmogorov Medal, the Moscow Mathematical Society Award, the Boltzmann Medal, the Dirac Medal, the Dannie Heineman Prize, the Wolf Prize, the Jürgen Moser Prize, the Henri Poincaré Prize, and more. -
Gaudin Models Associated to Classical Lie Algebras A
GAUDIN MODELS ASSOCIATED TO CLASSICAL LIE ALGEBRAS A Dissertation Submitted to the Faculty of Purdue University by Kang Lu In Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy August 2020 Purdue University Indianapolis, Indiana ii THE PURDUE UNIVERSITY GRADUATE SCHOOL STATEMENT OF DISSERTATION APPROVAL Dr. Evgeny Mukhin, Chair Department of Mathematical Sciences Dr. Alexander Its Department of Mathematical Sciences Dr. Roland Roeder Department of Mathematical Sciences Dr. Vitaly Tarasov Department of Mathematical Sciences Approved by: Dr. Evgeny Mukhin Head of the Graduate Program iii Dedicated to my parents and my wife Ziting Tang. iv ACKNOWLEDGMENTS I would like to express my deepest appreciation to my advisor Prof. Evgeny Mukhin for his guidance, support and persistent help throughout my time in graduate school and for introducing me to the world of representation theory and quantum integrable systems. I would like to extend my deepest gratitude to Prof. Vitaly Tarasov. I had great pleasure working with him and learned a lot from him. I sincerely appreciate his patient guidance and help. I also sincerely appreciate Prof. Its and Prof. Roeder for offering wonderful classes and for their effort and time in serving in my dissertation committee. Besides, I would like to thank Prof. Zhongmin Shen and Prof. Hanxiang Peng for useful suggestions. In addition, many thanks to the staff in the department for their assistance. Finally, I thank my parents and my wife Ziting Tang for their constant support, encouragement, and love throughout the years. v PREFACE This thesis is mainly based on three publications. Chapters 2 and 3 are based on the publications jointly with Evgeny Mukhin and Alexander Varchenko [LMV16] Kang Lu, E. -
Excerpts from Kolmogorov's Diary
Asia Pacific Mathematics Newsletter Excerpts from Kolmogorov’s Diary Translated by Fedor Duzhin Introduction At the age of 40, Andrey Nikolaevich Kolmogorov (1903–1987) began a diary. He wrote on the title page: “Dedicated to myself when I turn 80 with the wish of retaining enough sense by then, at least to be able to understand the notes of this 40-year-old self and to judge them sympathetically but strictly”. The notes from 1943–1945 were published in Russian in 2003 on the 100th anniversary of the birth of Kolmogorov as part of the opus Kolmogorov — a three-volume collection of articles about him. The following are translations of a few selected records from the Kolmogorov’s diary (Volume 3, pages 27, 28, 36, 95). Sunday, 1 August 1943. New Moon 6:30 am. It is a little misty and yet a sunny morning. Pusya1 and Oleg2 have gone swimming while I stay home being not very well (though my condition is improving). Anya3 has to work today, so she will not come. I’m feeling annoyed and ill at ease because of that (for the second time our Sunday “readings” will be conducted without Anya). Why begin this notebook now? There are two reasonable explanations: 1) I have long been attracted to the idea of a diary as a disciplining force. To write down what has been done and what changes are needed in one’s life and to control their implementation is by no means a new idea, but it’s equally relevant whether one is 16 or 40 years old. -
CURRICULUM VITAE November 2007 Hugo J
CURRICULUM VITAE November 2007 Hugo J. Woerdeman Professor and Department Head Office address: Home address: Department of Mathematics 362 Merion Road Drexel University Merion, PA 19066 Philadelphia, PA 19104 Phone: (610) 664-2344 Phone: (215) 895-2668 Fax: (215) 895-1582 E-mail: [email protected] Academic employment: 2005– Department of Mathematics, Drexel University Professor and Department Head (January 2005 – Present) 1989–2004 Department of Mathematics, College of William and Mary, Williamsburg, VA. Margaret L. Hamilton Professor of Mathematics (August 2003 – December 2004) Professor (July 2001 – December 2004) Associate Professor (September 1995 – July 2001) Assistant Professor (August 1989 – August 1995; on leave: ’89/90) 2002-03 Department of Mathematics, K. U. Leuven, Belgium, Visiting Professor Post-doctorate: 1989– 1990 University of California San Diego, Advisor: J. W. Helton. Education: Ph. D. degree in mathematics from Vrije Universiteit, Amsterdam, 1989. Thesis: ”Matrix and Operator Extensions”. Advisor: M. A. Kaashoek. Co-advisor: I. Gohberg. Doctoraal (equivalent of M. Sc.), Vrije Universiteit, Amsterdam, The Netherlands, 1985. Thesis: ”Resultant Operators and the Bezout Equation for Analytic Matrix Functions”. Advisor: L. Lerer Current Research Interests: Modern Analysis: Operator Theory, Matrix Analysis, Optimization, Signal and Image Processing, Control Theory, Quantum Information. Editorship: Associate Editor of SIAM Journal of Matrix Analysis and Applications. Guest Editor for a Special Issue of Linear Algebra and -
Discurso De Investidura Como Doctor “Honoris Causa” Del Excmo. Sr
Discurso de investidura como Doctor “Honoris Causa” del Excmo. Sr. Simon Kirwan Donaldson 20 de enero de 2017 Your Excellency Rector Andradas, Ladies and Gentlemen: It is great honour for me to receive the degree of Doctor Honoris Causa from Complutense University and I thank the University most sincerely for this and for the splendid ceremony that we are enjoying today. This University is an ancient institution and it is wonderful privilege to feel linked, through this honorary degree, to a long line of scholars reaching back seven and a half centuries. I would like to mention four names, all from comparatively recent times. First, Eduardo Caballe, a mathematician born in 1847 who was awarded a doctorate of Science by Complutense in 1873. Later, he was a professor in the University and, through his work and his students, had a profound influence in the development of mathematics in Spain, and worldwide. Second, a name that is familiar to all of us: Albert Einstein, who was awarded a doctorate Honoris Causa in 1923. Last, two great mathematicians from our era: Vladimir Arnold (Doctor Honoris Causa 1994) and Jean- Pierre Serre (2006). These are giants of the generation before my own from whom, at whose feet---metaphorically—I have learnt. Besides the huge honour of joining such a group, it is interesting to trace one grand theme running the work of all these four people named. The theme I have in mind is the interplay between notions of Geometry, Algebra and Space. Of course Geometry begins with the exploration of the space we live in—the space of everyday experience.