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Report for the Academic Year 1995
Institute /or ADVANCED STUDY REPORT FOR THE ACADEMIC YEAR 1994 - 95 PRINCETON NEW JERSEY Institute /or ADVANCED STUDY REPORT FOR THE ACADEMIC YEAR 1 994 - 95 OLDEN LANE PRINCETON • NEW JERSEY 08540-0631 609-734-8000 609-924-8399 (Fax) Extract from the letter addressed by the Founders to the Institute's Trustees, dated June 6, 1930. Newark, New jersey. It is fundamental in our purpose, and our express desire, that in the appointments to the staff and faculty, as well as in the admission of workers and students, no account shall be taken, directly or indirectly, of race, religion, or sex. We feel strongly that the spirit characteristic of America at its noblest, above all the pursuit of higher learning, cannot admit of any conditions as to personnel other than those designed to promote the objects for which this institution is established, and particularly with no regard whatever to accidents of race, creed, or sex. TABLE OF CONTENTS 4 BACKGROUND AND PURPOSE 5 • FOUNDERS, TRUSTEES AND OFFICERS OF THE BOARD AND OF THE CORPORATION 8 • ADMINISTRATION 11 REPORT OF THE CHAIRMAN 15 REPORT OF THE DIRECTOR 23 • ACKNOWLEDGMENTS 27 • REPORT OF THE SCHOOL OF HISTORICAL STUDIES ACADEMIC ACTIVITIES MEMBERS, VISITORS AND RESEARCH STAFF 36 • REPORT OF THE SCHOOL OF MATHEMATICS ACADEMIC ACTIVITIES MEMBERS AND VISITORS 42 • REPORT OF THE SCHOOL OF NATURAL SCIENCES ACADEMIC ACTIVITIES MEMBERS AND VISITORS 50 • REPORT OF THE SCHOOL OF SOCIAL SCIENCE ACADEMIC ACTIVITIES MEMBERS, VISITORS AND RESEARCH STAFF 55 • REPORT OF THE INSTITUTE LIBRARIES 57 • RECORD OF INSTITUTE EVENTS IN THE ACADEMIC YEAR 1994-95 85 • INDEPENDENT AUDITORS' REPORT INSTITUTE FOR ADVANCED STUDY: BACKGROUND AND PURPOSE The Institute for Advanced Study is an independent, nonprofit institution devoted to the encouragement of learning and scholarship. -
TWAS Fellowships Worldwide
CDC Round Table, ICTP April 2016 With science and engineering, countries can address challenges in agriculture, climate, health TWAS’s and energy. guiding principles 2 Food security Challenges Water quality for a Energy security new era Biodiversity loss Infectious diseases Climate change 3 A Globally, 81 nations fall troubling into the category of S&T- gap lagging countries. 48 are classified as Least Developed Countries. 4 The role of TWAS The day-to-day work of TWAS is focused in two critical areas: •Improving research infrastructure •Building a corps of PhD scholars 5 TWAS Research Grants 2,202 grants awarded to individuals and research groups (1986-2015) 6 TWAS’ AIM: to train 1000 PhD students by 2017 Training PhD-level scientists: •Researchers and university-level educators •Future leaders for science policy, business and international cooperation Rapidly growing opportunities P BRAZIL A K I N D I CA I RI A S AF TH T SOU A N M KENYA EX ICO C H I MALAYSIA N A IRAN THAILAND TWAS Fellowships Worldwide NRF, South Africa - newly on board 650+ fellowships per year PhD fellowships +460 Postdoctoral fellowships +150 Visiting researchers/professors + 45 17 Programme Partners BRAZIL: CNPq - National Council MALAYSIA: UPM – Universiti for Scientific and Technological Putra Malaysia WorldwideDevelopment CHINA: CAS - Chinese Academy of KENYA: icipe – International Sciences Centre for Insect Physiology and Ecology INDIA: CSIR - Council of Scientific MEXICO: CONACYT– National & Industrial Research Council on Science and Technology PAKISTAN: CEMB – National INDIA: DBT - Department of Centre of Excellence in Molecular Biotechnology Biology PAKISTAN: ICCBS – International Centre for Chemical and INDIA: IACS - Indian Association Biological Sciences for the Cultivation of Science PAKISTAN: CIIT – COMSATS Institute of Information INDIA: S.N. -
Kavli IPMU Annual 2014 Report
ANNUAL REPORT 2014 REPORT ANNUAL April 2014–March 2015 2014–March April Kavli IPMU Kavli Kavli IPMU Annual Report 2014 April 2014–March 2015 CONTENTS FOREWORD 2 1 INTRODUCTION 4 2 NEWS&EVENTS 8 3 ORGANIZATION 10 4 STAFF 14 5 RESEARCHHIGHLIGHTS 20 5.1 Unbiased Bases and Critical Points of a Potential ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙20 5.2 Secondary Polytopes and the Algebra of the Infrared ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙21 5.3 Moduli of Bridgeland Semistable Objects on 3- Folds and Donaldson- Thomas Invariants ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙22 5.4 Leptogenesis Via Axion Oscillations after Inflation ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙23 5.5 Searching for Matter/Antimatter Asymmetry with T2K Experiment ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ 24 5.6 Development of the Belle II Silicon Vertex Detector ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙26 5.7 Search for Physics beyond Standard Model with KamLAND-Zen ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙28 5.8 Chemical Abundance Patterns of the Most Iron-Poor Stars as Probes of the First Stars in the Universe ∙ ∙ ∙ 29 5.9 Measuring Gravitational lensing Using CMB B-mode Polarization by POLARBEAR ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ 30 5.10 The First Galaxy Maps from the SDSS-IV MaNGA Survey ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙32 5.11 Detection of the Possible Companion Star of Supernova 2011dh ∙ ∙ ∙ ∙ ∙ ∙ -
Arxiv:1404.2323V1 [Math.AG] 8 Apr 2014 Membranes and Sheaves
Membranes and Sheaves Nikita Nekrasov and Andrei Okounkov April 2014 Contents 1 A brief introduction 2 1.1 Overview.............................. 2 1.2 MotivationfromM-theory . 3 1.3 Planofthepaper ......................... 7 1.4 Acknowledgements ........................ 7 2 Contours of the conjectures 8 2.1 K-theorypreliminaries ...................... 8 2.2 Theindexsheaf.......................... 10 2.3 Comparison with Donaldson-Thomastheory . 15 2.4 Fields of 11-dimensional supergravity and degree zero DT counts 19 3 The DT integrand 24 3.1 Themodifiedvirtualstructuresheaf. 24 3.2 The interaction term Φ ...................... 28 arXiv:1404.2323v1 [math.AG] 8 Apr 2014 4 The index of membranes 33 4.1 Membranemoduli......................... 33 4.2 Deformationsofmembranes . 36 5 Examples 37 5.1 Reducedlocalcurves ....................... 37 5.2 Doublecurves........................... 39 5.3 Single interaction between smooth curves . 42 5.4 HigherrankDTcounts. .. .. 43 5.5 EngineeringhigherrankDTtheory . 45 1 6 Existence of square roots 49 6.1 Symmetricbundlesonsquares . 49 6.2 SquarerootsinDTtheory . 50 6.3 SquarerootsinM-theory. 52 7 Refined invariants 54 7.1 Actionsscalingthe3-form . 54 7.2 Localization for κ-trivialtori................... 56 7.3 Morsetheoryandrigidity . 60 8 Index vertex and refined vertex 61 8.1 Toric Calabi-Yau 3-folds . 61 8.2 Virtualtangentspacesatfixedpoints . 63 8.3 Therefinedvertex ........................ 66 A Appendix 70 A.1 Proofofthebalancelemma . 70 1 A brief introduction 1.1 Overview Our goal in this paper is to discuss a conjectural correspondence between enumerative geometry of curves in Calabi-Yau 5-folds Z and 1-dimensional sheaves on 3-folds X that are embedded in Z as fixed points of certain C×- actions. In both cases, the enumerative information is taken in equivariant K-theory, where the equivariance is with respect to all automorphisms of the problem. -
Arxiv:1512.05388V2 [Hep-Th] 2 Jan 2016 1
BPS/CFT CORRESPONDENCE: NON-PERTURBATIVE DYSON-SCHWINGER EQUATIONS AND qq-CHARACTERS NIKITA NEKRASOV Abstract. We study symmetries of quantum field theories involving topologically dis- tinct sectors of the field space. To exhibit these symmetries we define special gauge invariant observables, which we call the qq-characters. In the context of the BPS/CFT correspondence, using these observables, we derive an infinite set of Dyson-Schwinger- type relations. These relations imply that the supersymmetric partition functions in the presence of Ω-deformation and defects obey the Ward identities of two dimen- sional conformal field theory and its q-deformations. The details will be discussed in the companion papers. Contents 1. Introduction 4 1.1. Dyson-Schwinger equations 4 1.2. Non-perturbative Dyson-Schwinger identities 6 1.3. Organization of the presentation 8 1.4. Acknowledgements 10 2. The BPS/CFT correspondence 12 2.1. = 2 partition functions 12 2.2. DefectN operators and lower-dimensional theories 13 2.3. The Y- and X-observables 14 2.4. The physics of X-observables 14 arXiv:1512.05388v2 [hep-th] 2 Jan 2016 2.5. Hidden symmetries 17 2.6. Some notations. 17 2.7. Equivariant virtual Chern polynomials 22 3. Supersymmetric gauge theories 22 3.1. Quivers 22 3.2. Quivers with colors 22 3.3. The symmetry groups 22 3.4. The parameters of Lagrangian 24 3.5. The group H 25 3.6. Perturbative theory 26 3.7. Realizations of quiver theories 28 4. Integration over instanton moduli spaces 30 1 2 NIKITA NEKRASOV 4.1. Instanton partition function 30 4.2. -
FY 2008 WPI Project Progress Report World Premier International Research Center (WPI) Initiative
FY 2008 WPI Project Progress Report World Premier International Research Center (WPI) Initiative Host Institution The University of Tokyo Host Institution Head Hiroshi Komiyama Research Center Institute for the Physics and Mathematics of the Universe Center Director Hitoshi Murayama Summary of center project progress HyperSuprimeCam projects are making steady progress, and the MoU Institute for the Physics and Mathematics of the Universe (IPMU) has made to join SDSS-III experiment was signed. steady progress towards the stated goals. The numbers below refer to the (5) Honors and Awards. PI Ooguri received the 2009 Humboldt Research period between April 1, 2008 and March 31, 2009, unless stated otherwise. Award, and Prof. Sugimoto received the 2008 Kimura prize of (1) Organization. The number of administrative and research support staff theoretical physics. Assoc. Prof. Yoshida received the IUPAP Young has exceeded the proposed number of 30. The scientific staff is also Scientist Prize in computational physics, and Assoc. Prof. Komatsu steadily growing, from 63 to 125, well on track towards the proposed (joint appointment with Texas) received the same Prize in astrophysics. goal of 195 (March 2011). PI Nakahata received the 2008 Inoue Prize for Science. PI Inoue received the 2008 JSPS Prize. (2) Internationalization. The WPI program requires more than 30% of the researchers to be non-Japanese. Our current percentage is 48%, and (6) Interdisciplinary activities. As proposed, we hold daily tea at three has fulfilled the mandate. The most significant among the non-Japanese o’clock to encourage informal and interdisciplinary discussions. They members is one full and two associate professors who have moved from are well attended and create desired atmosphere. -
Breakthrough Prize in Mathematics Awarded to Terry Tao
156 Breakthrough Prize in Mathematics awarded to Terry Tao Our congratulations to Australian Mathematician Terry Tao, one of five inaugu- ral winners of the Breakthrough Prizes in Mathematics, announced on 23 June. Terry is based at the University of California, Los Angeles, and has been awarded the prize for numerous breakthrough contributions to harmonic analysis, combi- natorics, partial differential equations and analytic number theory. The Breakthrough Prize in Mathematics was launched by Mark Zuckerberg and Yuri Milner at the Breakthrough Prize ceremony in December 2013. The other winners are Simon Donaldson, Maxim Kontsevich, Jacob Lurie and Richard Tay- lor. All five recipients of the Prize have agreed to serve on the Selection Committee, responsible for choosing subsequent winners from a pool of candidates nominated in an online process which is open to the public. From 2015 onwards, one Break- through Prize in Mathematics will be awarded every year. The Breakthrough Prizes honor important, primarily recent, achievements in the categories of Fundamental Physics, Life Sciences and Mathematics. The prizes were founded by Sergey Brin and Anne Wojcicki, Mark Zuckerberg and Priscilla Chan, and Yuri and Julia Milner, and aim to celebrate scientists and generate excitement about the pursuit of science as a career. Laureates will receive their trophies and $3 million each in prize money at a televised award ceremony in November, designed to celebrate their achievements and inspire the next genera- tion of scientists. As part of the ceremony schedule, they also engage in a program of lectures and discussions. See https://breakthroughprize.org and http://www.nytimes.com/2014/06/23/us/ the-multimillion-dollar-minds-of-5-mathematical-masters.html? r=1 for further in- formation.. -
Model Building and SUSY Breaking on D-Branes
Model building and SUSY breaking on D-branes Dmitry Malyshev a dissertation presented to the faculty of princeton university in candidacy for the degree of doctor of philosophy recommended for acceptance by the department of physics Adviser: Herman Verlinde September 2008 c Copyright by Dmitry Malyshev, 2008. All rights reserved. Abstract In the recent years there has been an increase of the interest in applying the String theory to construct viable extensions of the Standard Model and to find stringy analogs of the known field theory models for supersymmetry breaking. In my dissertation I will focus on the constructions involving the D-branes at the Calabi-Yau singularities in type IIB string theory. The main motivations for this choice are: the decoupling of the D-brane field theory from the supergravity, the well established tools for deriving the field theories from the configurations of the D-branes, and the possibility of using the gauge-gravity correspondence in solving some non-perturbative aspects in the field theory. A construction of an extended supersymmetric Standard Model on a D3-brane at the del Pezzo 8 singularity is presented in the first part of the dissertation. In the second part we discuss the possible representations of the SUSY breaking models in String Theory and obtain the metastable SUSY breaking vacuum in a system of D-branes on the suspended pinch point singularity. The gauge mediation of this SUSY breaking model is described in details. In the simplest model the spectrum of particles in the visible sector has a split SUSY breaking, the sfermions are one order of magnitude heavier than the gauginos. -
Nikita Nekrasov 講義録
Nikita Nekrasov 講義録 December, 1998 講義録作成1 :橋本幸士, 岸本 功 (京大理) 目次 第 I 部 超共形ゲージ理論と AdS 超重力理論 2 1 Introduction と motivation 3 2 Orbifold 理論 6 3 時空の状況 12 4 Orbifold から conifold への変形 17 5 まとめ 19 第 II 部 N =2ゲージ理論における状態のカウント 21 6 導入 22 7 D3-プローブ上の理論 22 8M理論への持ち上げ/引き落とし 27 9 結論 39 1この講義録は「Workshop ”ゲージ理論の力学と弦双対性” 1998 年 12 月 16 日(水)–12月 18 日(金)東京工業大学国際交流会館」における Nekrasov 氏の講義に基づくものです。第 I 部が 16 日に、第 II 部が 18 日に行われました。 1 第 I 部 超共形ゲージ理論とAdS超重力理論 (SUPER)CONFORMAL GAUGE THEORIES AND ANTI-DE-SITTER SUPERGRAVITY2 Nikita Nekrasov 1. Introduction と motivation ——哲学, D-brane と付随した場の理論, 特異な幾何からの conformal 理論 2. Orbifold 理論 ——理論の構築(:gauge 群, matter の内容, (超)対称性), β 関数の計算, 摂動論の解析 3. 時空の状況 ——near-horizon limit, 超重力における変形 4. Orbifold から conifold への変形 ——場の理論の実現, Higgs branch の幾何, 時空解釈(conjecture) 2文献 [1, 2] に基づく。[3, 4, 5, 6, 7, 8] も見よ。 2 第 1 章 Introduction と motivation 双対性に関する動きの中でおそらく最も(そしておそらく唯一つの)重要な教訓は、面白い物理は面白い幾何に関係 しているという発想に立ち返るということである。Einstein の時代に比べての違いは、勿論量子的な物理量が古典的な 幾何を通じて表現されうるという仮定である。例えば、N =2SU(2) gauge 理論の有効結合定数(と長距離相関関数) は補佐的な楕円曲線 Eu の modular 変数 τ(u) を用いて表される: y2 =(x − u)(x2 − Λ4). (1) ここで u = hTrφ2i は真空の moduli 空間を label する。 u-plane θ(u) 4πi Eu: τ(u)= 2π + e2(u) vacuum 図 1: N =2SU(2) gauge 理論の moduli 空間。 物理から幾何、また逆に幾何から物理への変換を理解するのに必要不可欠な道具は D-brane である。D-brane に関し ての良い点は以下の二つである: (1) D-brane の上に弦が端点を持つので、いくつかの D-brane がお互いに重なるとその worldvolume 上に非可換 gauge boson が発生する。(2) D-brane は Ramond-Ramond 場の電荷を持っており、(適切な条 件の下で)弦理論における soliton として記述されうる。 (1) (2) 図 2: D-brane の二つの描像。(1) 開弦の端点としての D-brane、(2) 弦理論の soliton としての D-brane。 一般的な発想は、gauge 理論とそれに対応する soliton の背景を伝播する弦の理論を等しくするように、D-brane を用 いる、ということである。もし(IIB 型超弦理論で)N 枚の D3-brane が平坦な空間内でお互いに重なっていると、この 重なった brane は二つの記述法を持つ: 1. -
String-Math 2012
Volume 90 String-Math 2012 July 16–21, 2012 Universitat¨ Bonn, Bonn, Germany Ron Donagi Sheldon Katz Albrecht Klemm David R. Morrison Editors Volume 90 String-Math 2012 July 16–21, 2012 Universitat¨ Bonn, Bonn, Germany Ron Donagi Sheldon Katz Albrecht Klemm David R. Morrison Editors Volume 90 String-Math 2012 July 16–21, 2012 Universitat¨ Bonn, Bonn, Germany Ron Donagi Sheldon Katz Albrecht Klemm David R. Morrison Editors 2010 Mathematics Subject Classification. Primary 11G55, 14D21, 14F05, 14J28, 14M30, 32G15, 53D18, 57M27, 81T40. 83E30. Library of Congress Cataloging-in-Publication Data String-Math (Conference) (2012 : Bonn, Germany) String-Math 2012 : July 16-21, 2012, Universit¨at Bonn, Bonn, Germany/Ron Donagi, Sheldon Katz, Albrecht Klemm, David R. Morrison, editors. pages cm. – (Proceedings of symposia in pure mathematics; volume 90) Includes bibliographical references. ISBN 978-0-8218-9495-8 (alk. paper) 1. Geometry, Algebraic–Congresses. 2. Quantum theory– Mathematics–Congresses. I. Donagi, Ron, editor. II. Katz, Sheldon, 1956- editor. III. Klemm, Albrecht, 1960- editor. IV. Morrison, David R., 1955- editor. V. Title. QA564.S77 2012 516.35–dc23 2015017523 DOI: http://dx.doi.org/10.1090/pspum/090 Color graphic policy. Any graphics created in color will be rendered in grayscale for the printed version unless color printing is authorized by the Publisher. In general, color graphics will appear in color in the online version. Copying and reprinting. Individual readers of this publication, and nonprofit libraries acting for them, are permitted to make fair use of the material, such as to copy select pages for use in teaching or research. Permission is granted to quote brief passages from this publication in reviews, provided the customary acknowledgment of the source is given. -
An Interview with Martin Davis
Notices of the American Mathematical Society ISSN 0002-9920 ABCD springer.com New and Noteworthy from Springer Geometry Ramanujan‘s Lost Notebook An Introduction to Mathematical of the American Mathematical Society Selected Topics in Plane and Solid Part II Cryptography May 2008 Volume 55, Number 5 Geometry G. E. Andrews, Penn State University, University J. Hoffstein, J. Pipher, J. Silverman, Brown J. Aarts, Delft University of Technology, Park, PA, USA; B. C. Berndt, University of Illinois University, Providence, RI, USA Mediamatics, The Netherlands at Urbana, IL, USA This self-contained introduction to modern This is a book on Euclidean geometry that covers The “lost notebook” contains considerable cryptography emphasizes the mathematics the standard material in a completely new way, material on mock theta functions—undoubtedly behind the theory of public key cryptosystems while also introducing a number of new topics emanating from the last year of Ramanujan’s life. and digital signature schemes. The book focuses Interview with Martin Davis that would be suitable as a junior-senior level It should be emphasized that the material on on these key topics while developing the undergraduate textbook. The author does not mock theta functions is perhaps Ramanujan’s mathematical tools needed for the construction page 560 begin in the traditional manner with abstract deepest work more than half of the material in and security analysis of diverse cryptosystems. geometric axioms. Instead, he assumes the real the book is on q- series, including mock theta Only basic linear algebra is required of the numbers, and begins his treatment by functions; the remaining part deals with theta reader; techniques from algebra, number theory, introducing such modern concepts as a metric function identities, modular equations, and probability are introduced and developed as space, vector space notation, and groups, and incomplete elliptic integrals of the first kind and required. -
Mini-Symposium on String Theory and M-Theory
Mini-Symposium on String Theory and M-Theory Chair: Michael R. Douglas Duiliu-EmanuelDiaconescu JaumeGomis ChrisM.Hull AlbrechtKlemm Jos´eM.F.Labastida MarcosMarin˜ o NikitaNekrasov ChristophSchweigert AngelM.Uranga Duiliu-Emanuel Diaconescu Institute for Advanced Study, Princeton K-theory from M-theory Wednesday, 12.30 – 13.00, Room B I report on joint work with Gregory Moore and Edward Witten —“E8 Gauge Theory, and a Derivation of K-Theory from M-Theory”. It has become clear in recent years that type II string theories contain nonperturbative objects —called D-branes— which support gauge fields. From a more abstract point of view, D-brane charges are classified by K-theory classes of the space- time manifold X. Since D-branes are charged under Ramond-Ramond fields, E. Witten and then G. Moore and E. Witten proposed a K-theoretic interpretation of Ramond-Ramond fluxes themselves. This is more striking, as the RR fields are states in the perturbative closed string spectrum which a priori have no connection with vector bundles and K-theory. In the present work, we show that this proposal is consistent with M-theory. The main idea is a detailed comparison of the leading terms in the long distance partition function of M-theory and IIA string theory. The analysis relies heavily on index theory and homotopy theory techniques. It is found a precise agreement which confirms the internal consistency of M-theory, as well as the validity of the K-theoretic formalism in string theory. Jaume Gomis Caltech University D-branes in nongeometric phases of string theory Tuesday, 12.00 – 12.30, Room B Recent progress in string theory hinges upon our improved understanding of its nonperturbative states.