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Ζ−1 Using Theorem 1.2
UC San Diego UC San Diego Electronic Theses and Dissertations Title Ihara zeta functions of irregular graphs Permalink https://escholarship.org/uc/item/3ws358jm Author Horton, Matthew D. Publication Date 2006 Peer reviewed|Thesis/dissertation eScholarship.org Powered by the California Digital Library University of California UNIVERSITY OF CALIFORNIA, SAN DIEGO Ihara zeta functions of irregular graphs A dissertation submitted in partial satisfaction of the requirements for the degree Doctor of Philosophy in Mathematics by Matthew D. Horton Committee in charge: Professor Audrey Terras, Chair Professor Mihir Bellare Professor Ron Evans Professor Herbert Levine Professor Harold Stark 2006 Copyright Matthew D. Horton, 2006 All rights reserved. The dissertation of Matthew D. Horton is ap- proved, and it is acceptable in quality and form for publication on micro¯lm: Chair University of California, San Diego 2006 iii To my wife and family Never hold discussions with the monkey when the organ grinder is in the room. |Sir Winston Churchill iv TABLE OF CONTENTS Signature Page . iii Dedication . iv Table of Contents . v List of Figures . vii List of Tables . viii Acknowledgements . ix Vita ...................................... x Abstract of the Dissertation . xi 1 Introduction . 1 1.1 Preliminaries . 1 1.2 Ihara zeta function of a graph . 4 1.3 Simplifying assumptions . 8 2 Poles of the Ihara zeta function . 10 2.1 Bounds on the poles . 10 2.2 Relations among the poles . 13 3 Recovering information . 17 3.1 The hope . 17 3.2 Recovering Girth . 18 3.3 Chromatic polynomials and Ihara zeta functions . 20 4 Relations among Ihara zeta functions . -
Ihara Zeta Functions
Audrey Terras 2/16/2004 fun with zeta and L- functions of graphs Audrey Terras U.C.S.D. February, 2004 IPAM Workshop on Automorphic Forms, Group Theory and Graph Expansion Introduction The Riemann zeta function for Re(s)>1 ∞ 1 −1 ζ ()sp== 1 −−s . ∑ s ∏ () n=1 n pprime= Riemann extended to all complex s with pole at s=1. Functional equation relates value at s and 1-s Riemann hypothesis duality between primes and complex zeros of zeta See Davenport, Multiplicative Number Theory. 1 Audrey Terras 2/16/2004 Graph of |Zeta| Graph of z=| z(x+iy) | showing the pole at x+iy=1 and the first 6 zeros which are on the line x=1/2, of course. The picture was made by D. Asimov and S. Wagon to accompany their article on the evidence for the Riemann hypothesis as of 1986. A. Odlyzko’s Comparison of Spacings of Zeros of Zeta and Eigenvalues of Random Hermitian Matrix. See B. Cipra, What’s Happening in Math. Sciences, 1998-1999. 2 Audrey Terras 2/16/2004 Dedekind zeta of an We’ll algebraic number field F, say where primes become prime more ideals p and infinite product of about number terms field (1-Np-s)-1, zetas Many Kinds of Zeta Np = norm of p = #(O/p), soon O=ring of integers in F but not Selberg zeta Selberg zeta associated to a compact Riemannian manifold M=G\H, H = upper half plane with arc length ds2=(dx2+dy2)y-2 , G=discrete group of real fractional linear transformations primes = primitive closed geodesics C in M of length −+()()sjν C ν(C), Selberg Zs()=− 1 e (primitive means only go Zeta = ∏ ∏( ) around once) []Cj≥ 0 Reference: A.T., Harmonic Analysis on Symmetric Duality between spectrum ∆ on M & lengths closed geodesics in M Spaces and Applications, I. -
Torification and Factorization of Birational Maps 3
TORIFICATION AND FACTORIZATION OF BIRATIONAL MAPS DAN ABRAMOVICH, KALLE KARU, KENJI MATSUKI, AND JAROSLAW WLODARCZYK Abstract. Building on work of the fourth author in [69], we prove the weak factorization conjecture for birational maps in characteristic zero: a birational map between complete nonsingular varieties over an algebraically closed field K of characteristic zero is a composite of blowings up and blowings down with smooth centers. Contents 0. Introduction 1 1. Preliminaries 5 2. Birational Cobordisms 10 3. Torification 16 4. A proof of the weak factorization theorem 22 5. Generalizations 24 6. Problems related to weak factorization 27 References 28 0. Introduction We work over an algebraically closed field K of characteristic 0. We denote the multiplicative group of K by K∗. 0.1. Statement of the main result. The purpose of this paper is to give a proof for the following weak factorization conjecture of birational maps. We note that another proof of this theorem was given by the fourth author in [70]. See section 0.12 for a brief comparison of the two approaches. Theorem 0.1.1 (Weak Factorization). Let φ : X1 99K X2 be a birational map between complete nonsingular algebraic varieties X1 and X2 over an algebraically closed field K of characteristic zero, and let U ⊂ X1 be an open set where φ is an isomorphism. Then φ can be factored into a sequence of blowings up and blowings arXiv:math/9904135v4 [math.AG] 31 May 2000 down with smooth irreducible centers disjoint from U, namely, there exists a sequence of birational maps between complete nonsingular algebraic varieties ϕ1 ϕ2 ϕi ϕi+1 ϕi+2 ϕl−1 ϕl X1 = V0 99K V1 99K · · · 99K Vi 99K Vi+1 99K · · · 99K Vl−1 99K Vl = X2 where 1. -
Algebraic Geometry of Topological Spaces I 3
ALGEBRAIC GEOMETRY OF TOPOLOGICAL SPACES I GUILLERMO CORTINAS˜ AND ANDREAS THOM Abstract. We use techniques from both real and complex algebraic geometry to study K- theoretic and related invariants of the algebra C(X) of continuous complex-valued functions on a compact Hausdorff topological space X. For example, we prove a parametrized version of a theorem of Joseph Gubeladze; we show that if M is a countable, abelian, cancella- tive, torsion-free, seminormal monoid, and X is contractible, then every finitely generated n projective module over C(X)[M] is free. The particular case M = N0 gives a parametrized version of the celebrated theorem proved independently by Daniel Quillen and Andrei Suslin that finitely generated projective modules over a polynomial ring over a field are free. The conjecture of Jonathan Rosenberg which predicts the homotopy invariance of the negative algebraic K-theory of C(X) follows from the particular case M = Zn. We also give alge- braic conditions for a functor from commutative algebras to abelian groups to be homotopy invariant on C∗-algebras, and for a homology theory of commutative algebras to vanish on C∗-algebras. These criteria have numerous applications. For example, the vanishing cri- terion applied to nil-K-theory implies that commutative C∗-algebras are K-regular. As another application, we show that the familiar formulas of Hochschild-Kostant-Rosenberg and Loday-Quillen for the algebraic Hochschild and cyclic homology of the coordinate ring of a smooth algebraic variety remain valid for the algebraic Hochschild and cyclic homology of C(X). Applications to the conjectures of Be˘ılinson-Soul´eand Farrell-Jones are also given. -
Notices of the American Mathematical Society
• ISSN 0002-9920 March 2003 Volume 50, Number 3 Disks That Are Double Spiral Staircases page 327 The RieITlann Hypothesis page 341 San Francisco Meeting page 423 Primitive curve painting (see page 356) Education is no longer just about classrooms and labs. With the growing diversity and complexity of educational programs, you need a software system that lets you efficiently deliver effective learning tools to literally, the world. Maple® now offers you a choice to address the reality of today's mathematics education. Maple® 8 - the standard Perfect for students in mathematics, sciences, and engineering. Maple® 8 offers all the power, flexibility, and resources your technical students need to manage even the most complex mathematical concepts. MapleNET™ -- online education ,.u A complete standards-based solution for authoring, nv3a~ _r.~ .::..,-;.-:.- delivering, and managing interactive learning modules \~.:...br *'r¥'''' S\l!t"AaITI(!\pU;; ,"", <If through browsers. Derived from the legendary Maple® .Att~~ .. <:t~~::,/, engine, MapleNefM is the only comprehensive solution "f'I!hlislJer~l!'Ct"\ :5 -~~~~~:--r---, for distance education in mathematics. Give your institution and your students cornpetitive edge. For a FREE 3D-day Maple® 8 Trial CD for Windows®, or to register for a FREE MapleNefM Online Seminar call 1/800 R67.6583 or e-mail [email protected]. ADVANCING MATHEMATICS WWW.MAPLESOFT.COM I [email protected]\I I WWW.MAPLEAPPS.COM I NORTH AMERICAN SALES 1/800 267. 6583 © 2003 Woter1oo Ma')Ir~ Inc Maple IS (J y<?glsterc() crademork of Woterloo Maple he Mar)leNet so troc1ema'k of Woter1oc' fV'lop'e Inr PII other trcde,nork$ (ye property o~ their respective ('wners Generic Polynomials Constructive Aspects of the Inverse Galois Problem Christian U. -
Graphs: Random, Chaos, and Quantum
Graphs: Random, Chaos, and Quantum Matilde Marcolli Fields Institute Program on Geometry and Neuroscience and MAT1845HS: Introduction to Fractal Geometry and Chaos University of Toronto, March 2020 Matilde Marcolli Graphs: Random, Chaos, and Quantum Some References Alex Fornito, Andrew Zalesky, Edward Bullmore, Fundamentals of Brain Network Analysis, Elsevier, 2016 Olaf Sporns, Networks of the Brain, MIT Press, 2010 Olaf Sporns, Discovering the Human Connectome, MIT Press, 2012 Fan Chung, Linyuan Lu, Complex Graphs and Networks, American Mathematical Society, 2004 L´aszl´oLov´asz, Large Networks and Graph Limits, American Mathematical Society, 2012 Matilde Marcolli Graphs: Random, Chaos, and Quantum Graphs G = (V ; E;@) • V = V (G) set of vertices (nodes) • E = E(G) set of edges (connections) • boundary map @ : E(G) ! V (G) × V (G), boundary vertices @(e) = fv; v 0g • directed graph (oriented edges): source and target maps s : E(G) ! V (G); t : E(G) ! V (G);@(e) = fs(e); t(e)g • looping edge: s(e) = t(e) starts and ends at same vertex; parallel edges: e 6= e0 with @(e) = @(e0) • simplifying assumption: graphs G with no parallel edges and no looping edges (sometimes assume one or the other) • additional data: label functions fV : V (G) ! LV and fE : E(G) ! LE to sets of vertex and edge labels LV and LE Matilde Marcolli Graphs: Random, Chaos, and Quantum Examples of Graphs Matilde Marcolli Graphs: Random, Chaos, and Quantum Network Graphs (Example from Facebook) Matilde Marcolli Graphs: Random, Chaos, and Quantum Increasing Randomness rewiring -
New York Journal of Mathematics Lang's Conjectures, Fibered
New York Journal of Mathematics New York J. Math. 2 (1996) 20–34. Lang’s Conjectures, Fibered Powers, and Uniformity Dan Abramovich and Jos´e Felipe Voloch Abstract. We prove that the fibered power conjecture of Caporaso et al. (Con- jecture H, [CHM], §6) together with Lang’s conjecture implies the uniformity of rational points on varieties of general type, as predicted in [CHM]; a few applications on the arithmetic and geometry of curves are stated. In an opposite direction, we give counterexamples to some analogous results in positive characteristic. We show that curves that change genus can have arbitrarily many rational points; and that curves over Fp(t) can have arbitrarily many Frobenius orbits of non-constant points. Contents 1. Introduction 21 1.1. A Few Conjectures of Lang 21 1.2. The Fibered Power Conjecture 22 1.3. Summary of Results on the Implication Side 22 1.4. Summary of Results: Examples in Positive Characteristic 24 1.5. Acknowledgments 25 2. Proof of Theorem 1.5 25 2.1. Preliminaries 25 2.2. Prolongable Points 25 2.3. Proof of Theorem 1.5 26 3. A Few Refinements and Applications in Arithmetic and Geometry 26 3.1. Proof of Theorem 1.6 26 3.2. Uniformity in Terms of the Degree of an Extension 27 3.3. The Geometric Case 28 4. Examples in Positive Characteristic 30 4.1. Curves that Change Genus 30 Received December 20, 1995. Mathematics Subject Classification. 14G; 11G. Key words and phrases. arithmetic geometry, Lang’s conjecture, rational points. Abramovich partially supported by NSF grant DMS-9503276. -
Quillen's Work in Algebraic K-Theory
J. K-Theory 11 (2013), 527–547 ©2013 ISOPP doi:10.1017/is012011011jkt203 Quillen’s work in algebraic K-theory by DANIEL R. GRAYSON Abstract We survey the genesis and development of higher algebraic K-theory by Daniel Quillen. Key Words: higher algebraic K-theory, Quillen. Mathematics Subject Classification 2010: 19D99. Introduction This paper1 is dedicated to the memory of Daniel Quillen. In it, we examine his brilliant discovery of higher algebraic K-theory, including its roots in and genesis from topological K-theory and ideas connected with the proof of the Adams conjecture, and his development of the field into a complete theory in just a few short years. We provide a few references to further developments, including motivic cohomology. Quillen’s main work on algebraic K-theory appears in the following papers: [65, 59, 62, 60, 61, 63, 55, 57, 64]. There are also the papers [34, 36], which are presentations of Quillen’s results based on hand-written notes of his and on communications with him, with perhaps one simplification and several inaccuracies added by the author. Further details of the plus-construction, presented briefly in [57], appear in [7, pp. 84–88] and in [77]. Quillen’s work on Adams operations in higher algebraic K-theory is exposed by Hiller in [45, sections 1-5]. Useful surveys of K-theory and related topics include [81, 46, 38, 39, 67] and any chapter in Handbook of K-theory [27]. I thank Dale Husemoller, Friedhelm Waldhausen, Chuck Weibel, and Lars Hesselholt for useful background information and advice. 1. -
References Is Provisional, and Will Grow (Or Shrink) As the Course Progresses
Note: This list of references is provisional, and will grow (or shrink) as the course progresses. It will never be comprehensive. See also the references (and the book) in the online version of Weibel's K- Book [40] at http://www.math.rutgers.edu/ weibel/Kbook.html. References [1] Armand Borel and Jean-Pierre Serre. Le th´eor`emede Riemann-Roch. Bull. Soc. Math. France, 86:97{136, 1958. [2] A. K. Bousfield. The localization of spaces with respect to homology. Topology, 14:133{150, 1975. [3] A. K. Bousfield and E. M. Friedlander. Homotopy theory of Γ-spaces, spectra, and bisimplicial sets. In Geometric applications of homotopy theory (Proc. Conf., Evanston, Ill., 1977), II, volume 658 of Lecture Notes in Math., pages 80{130. Springer, Berlin, 1978. [4] Kenneth S. Brown and Stephen M. Gersten. Algebraic K-theory as gen- eralized sheaf cohomology. In Algebraic K-theory, I: Higher K-theories (Proc. Conf., Battelle Memorial Inst., Seattle, Wash., 1972), pages 266{ 292. Lecture Notes in Math., Vol. 341. Springer, Berlin, 1973. [5] William Dwyer, Eric Friedlander, Victor Snaith, and Robert Thoma- son. Algebraic K-theory eventually surjects onto topological K-theory. Invent. Math., 66(3):481{491, 1982. [6] Eric M. Friedlander and Daniel R. Grayson, editors. Handbook of K- theory. Vol. 1, 2. Springer-Verlag, Berlin, 2005. [7] Ofer Gabber. K-theory of Henselian local rings and Henselian pairs. In Algebraic K-theory, commutative algebra, and algebraic geometry (Santa Margherita Ligure, 1989), volume 126 of Contemp. Math., pages 59{70. Amer. Math. Soc., Providence, RI, 1992. [8] Henri Gillet and Daniel R. -
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. -
Prize Is Awarded Every Three Years at the Joint Mathematics Meetings
AMERICAN MATHEMATICAL SOCIETY LEVI L. CONANT PRIZE This prize was established in 2000 in honor of Levi L. Conant to recognize the best expository paper published in either the Notices of the AMS or the Bulletin of the AMS in the preceding fi ve years. Levi L. Conant (1857–1916) was a math- ematician who taught at Dakota School of Mines for three years and at Worcester Polytechnic Institute for twenty-fi ve years. His will included a bequest to the AMS effective upon his wife’s death, which occurred sixty years after his own demise. Citation Persi Diaconis The Levi L. Conant Prize for 2012 is awarded to Persi Diaconis for his article, “The Markov chain Monte Carlo revolution” (Bulletin Amer. Math. Soc. 46 (2009), no. 2, 179–205). This wonderful article is a lively and engaging overview of modern methods in probability and statistics, and their applications. It opens with a fascinating real- life example: a prison psychologist turns up at Stanford University with encoded messages written by prisoners, and Marc Coram uses the Metropolis algorithm to decrypt them. From there, the article gets even more compelling! After a highly accessible description of Markov chains from fi rst principles, Diaconis colorfully illustrates many of the applications and venues of these ideas. Along the way, he points to some very interesting mathematics and some fascinating open questions, especially about the running time in concrete situ- ations of the Metropolis algorithm, which is a specifi c Monte Carlo method for constructing Markov chains. The article also highlights the use of spectral methods to deduce estimates for the length of the chain needed to achieve mixing. -
Martin's Axiom
Chapter 14 Martin’s Axiom In this chapter, we shall introduce a set-theoretic axiom, known as Martin’s Axiom, which is independent of ZFC. In the previous chapter we have compared forcing extensions with group extensions. Similarly, we could also compare forcing exten- sions with field extensions. Now, if we start, for example, with the field of rational numbers Q and extend Q step by step with algebraic extensions, we finally obtain an algebraic closure F of Q. Since F is algebraically closed, we cannot extend F with an algebraic extension. With respect to forcing extensions, we have a somewhat similar situation: If we start, for example, with Gödel’s model L, which is a model of ZFC + CH, and extend L step by step with forcing notions of a certain type, we finally obtain a model of ZFC which cannot be extended by a forcing notion of that type. The model we obtain in this way is a model in which Martin’s Axiom holds. In other words, models in which Martin’s Axiom holds are closed under certain forcing extensions, like algebraically closed fields are closed under algebraic extensions. As a matter of fact we would like to mention that in the presence of the Continuum Hypothesis, Martin’s Axiom is vacuously true. However, if the Continuum Hypothesis fails, then Martin’s Axiom becomes an interesting combinatorial statement as well as an important tool in Combinatorics which has many applications in Topology, but also in areas like Analysis and Algebra (see RELATED RESULTS 83 & 84). Filters on Partially Ordered Sets Below, we introduce the standard terminology of partially ordered sets, as it is used in forcing constructions.