ON CERTAIN CHARACTER SUMS OVER Fq[T] 1. Introduction In

Total Page:16

File Type:pdf, Size:1020Kb

ON CERTAIN CHARACTER SUMS OVER Fq[T] 1. Introduction In PROCEEDINGS OF THE AMERICAN MATHEMATICAL SOCIETY Volume 126, Number 3, March 1998, Pages 647{652 S 0002-9939(98)04582-1 ON CERTAIN CHARACTER SUMS OVER Fq[T ] CHIH-NUNG HSU (Communicated by Dennis A. Hejhal) Abstract. Let Fq be the finite field with q elements and let A denote the ring of polynomials in one variable with coefficients in Fq .LetPbe a monic polynomial irreducible in A. We obtain a bound for the least degree of a monic polynomial irreducible in A (q odd) which is a quadratic non-residue modulo P . We also find a bound for the least degree of a monic polynomial irreducible in A which is a primitive root modulo P . 1. Introduction In [1], on the assumption of the Extended Riemann Hypothesis, Ankeny proved that the least positive quadratic non-residue of the prime k is O((log k)2)andthe ν(k 1) ν(k 1) 2 least positive primitive root (mod k)isO (2 − log k(log 2 − log k)) ,where ν(k 1) denotes the number of distinct prime{ factors of k 1. } − − Let Fq be the finite field with q elements and let A denote the ring of polynomials in one variable with coefficients in Fq.LetPbe a monic irreducible in A.Inthis note, we establish the following results: (1) When q is odd, the least degree of a monic irreducible in A which is a quadratic non-residue modulo P is less than 2 + 2 logq(1 + deg P ) (corollary 2:2). In fact, this result is deduced from a more general situation (proposition 2:1). (2) The least degree of a monic irreducible in A which is a primitive root modulo deg P qdeg P 1 P is O( log deg P ) (theorem 3:1). Moreover, if q 1− is a prime number, then q − the least degree of a monic irreducible primitive root modulo P is less than 8+2logqdeg P (proposition 3:1). The above results will be deduced from a character sum estimate (theorem 2:1) due to Effinger and Hayes [3], Chapter 5. 2. The least positive quadratic non-residues Let Fq denote the finite field with q elements and let A denote the ring of polyno- mials in one variable T with coefficients in Fq.WedenotebyA+the set consisting (n) of all positive (monic) polynomials in A,andbyA+ the set consisting of all pos- itive polynomials in A+ of degree n. We may write any element f of A in the Received by the editors August 20, 1996. 1991 Mathematics Subject Classification. Primary 11A07; Secondary 11L40, 11N05. Key words and phrases. Riemann Hypothesis, quadratic non-residues, primitive roots. c 1998 American Mathematical Society 647 License or copyright restrictions may apply to redistribution; see https://www.ams.org/journal-terms-of-use 648 CHIH-NUNG HSU form d i f = aiT with ai Fq and ad =0: ∈ 6 i=0 X The degree of f is defined by deg f = d, and the valuation of f is defined by f = qd. | | It is known that the number πn of all positive irreducibles in A+ of degree n satisfies n n q n q (1) q 2 +1 π : n − ≤ n ≤ n Suppose that ∆ is a positive polynomial in A+. A character χ modulo ∆ is a group homomorphism χ :(A=∆)× C×. We define χ(f)=0if(f;∆) = 1 and define → 6 πn(χ)by πn(χ)= χ(P ): irreducible P A(n) X ∈ + These characters modulo ∆ can be identified as the idele class characters of Dirichlet type for the rational function field Fq(T ) (cf. [3], Exercise 2 of Section 5.1). Theorem 2.1. Let χ be a non-trivial character modulo ∆.Then n q 2 π(χ) (deg ∆ + 1) : | n |≤ · n Proof. Let m(χ) be the conductor of the idele class character χ. It follows from [3], Exercise 2 of Section 5.1, that m(χ) ∆ifχis ramified at and m(χ) ∆ifχ is unramified at . From [3], theorem|∞ 5.7, we know that ∞ | ∞ n q2 π (χ) deg m(χ) λ(χ)+2 ; | n |≤{ − }· n where λ(χ)=2ifχis ramified at and λ(χ)=1ifχis unramified at .This completes the proof. ∞ ∞ Theorem 2.2. Let χ be a non-trivial character modulo ∆ and let the complex number ξ with ξ =1be a value of the character χ . If a positive integer n satisfies | | 1+2log 1+deg ∆ for 5 q √q 2 q ; − ≥ n 2+2log (1+deg∆) for q =3;4; ≥ 8 q > <5+2logq(1+deg∆) for q =2; > (n) there then exists at least: one positive irreducible P in A+ such that (P; ∆) = 1 and χ(P ) = ξ. 6 Proof. Suppose that χ(P )=ξfor all positive irreducible P in A with deg P = n and (P; ∆) = 1. By the assumption, we have π deg ∆ π (χ): n − ≤| n | Using (1), we get n q n q 2 deg ∆ <π deg ∆; n − − n− License or copyright restrictions may apply to redistribution; see https://www.ams.org/journal-terms-of-use ON CERTAIN CHARACTER SUMS OVER Fq[T ] 649 and by theorem 2:1, we obtain n q 2 π (χ) (deg ∆ + 1) : | n |≤ · n Combining these, we obtain (under the above assumption) n n q n q 2 (2) q 2 deg ∆ < (deg ∆ + 1) : n − − · n If 1+2log 1+deg ∆ and 5, then we have n q √q 2 q ≥ − ≥ 1+deg∆ √q 2 n 1 −2 n − 1;q n: q2 ≤ √q ≤ ≥ This implies that n n 1 n 1 q 2 deg ∆ (√q 2) q −2 q −2 1 n − · + 2 2 n − − q 2 ≥ n · n − ! 1+deg∆ 1 +0 (deg ∆ + 1) : ≥ n ≥ · n Thus we obtain n n q n q 2 q 2 deg ∆ (deg ∆ + 1) : n − − ≥ · n This contradicts (2); hence it contradicts the assumption. There thus exists at least (n) one positive irreducible P in A+ such that (P; ∆) = 1 and χ(P ) = ξ. The proofs of the other cases are similar. 6 Corollary 2.1. Let χ be a non-trivial character modulo ∆.Ifq 5and deg ∆ ≥ (2) ≤ q 2√q 1, then there exists at least one positive irreducible P in A+ such that χ(−P ) =1−. 6 Proof. This follows immediately from theorem 2:2. If ∆ = P is a positive irreducible in A+, we then have the following: Proposition 2.1. Let χ be a non-trivial character modulo P and let the complex number ξ with ξ =1be a value of the character χ. If a positive integer n satisfies | | 1+2log 1+deg P for 4 q √q 1 q ; − ≥ (3) n 2+2log (1+degP) for q =3; ≥ 8 q > <4+2logq(1+degP) for q =2; > (n) there then exists at least: one positive irreducible P 0 in A such that P 0 = P and + 6 χ(P 0) = ξ. 6 Proof. The proof is a modification of the proof of theorem 2:2. Corollary 2.2. Let P be a positive irreducible in A+ (q odd). If n satisfies the condition (3), then there exists at least one positive irreducible in A+ of degree n which is a quadratic non-residue modulo P and at least one positive irreducible in A+ of degree n which is a quadratic residue modulo P . License or copyright restrictions may apply to redistribution; see https://www.ams.org/journal-terms-of-use 650 CHIH-NUNG HSU Proof. In proposition 2:1, let χ be the quadratic symbol for A (cf. [2]). The corollary then follows immediately. Corollary 2.3. Let P be a positive irreducible in A+, and let the positive integer d divide P 1.Ifnsatisfies the condition (3), there then exists at least one positive | |− irreducible in A+ of degree n which is a d-th power non-residue modulo P . Proof. Since the unit group (A=P A)× is a cyclic group, its character group is cyclic of order P 1. This corollary then follows immediately from d P 1and proposition 2:1.| |− || |− Let norm be the norm homomorphism of (A=P A)× onto Fq×,wherePis a positive irreducible in A+.Letχ:Fq× C×be any non-trivial character. Then, by proposition 2:1, we also have → Corollary 2.4. If n satisfies the condition (3), there then exists at least one posi- tive irreducible P 0 in A+ of degree n such that χ norm(P 0) =1. ◦ 6 3. The least positive primitive roots Let P be a positive irreducible in A+ with deg P 2. We say that a polynomial ¯ ≥ P 0 is a primitive root modulo P if P 0 is a generator of the cyclic group (A=P A)×, ¯ where P 0 is the canonical image of P 0 in A=P A. The purpose of this section is to find a bound for the least degree of a positive irreducible primitive root modulo P . Theorem 3.1. There exists a positive number c such that for any positive irre- deg P ducible P in A+,ifn c log deg , one can find at least one positive irreducible ≥ · q P of degree n which is a primitive root modulo P . Proof. Since (A=P A)× is a cyclic group of order P 1, the group CP consisting of all characters modulo P is also a cyclic group of| order|− P 1. If m is a positive integer such that m ( P 1), then| it|− is known that for any | | |− P 0 A ∈ P 1 | |− m if P 0 m 1(modP); χ(P0)= ≡ m 0otherwise; χ C ,χ =χ0 ( ∈ PX where χ0 is the trivial character modulo P .
Recommended publications
  • UC San Diego Electronic Theses and Dissertations
    UC San Diego UC San Diego Electronic Theses and Dissertations Title Norm-Euclidean Galois fields Permalink https://escholarship.org/uc/item/359664zv Author McGown, Kevin Joseph Publication Date 2010 Peer reviewed|Thesis/dissertation eScholarship.org Powered by the California Digital Library University of California UNIVERSITY OF CALIFORNIA, SAN DIEGO Norm-Euclidean Galois Fields A dissertation submitted in partial satisfaction of the requirements for the degree Doctor of Philosophy in Mathematics by Kevin Joseph McGown Committee in charge: Professor Harold Stark, Chair Professor Wee Teck Gan Professor Ronald Graham Professor Russell Impagliazzo Professor Cristian Popescu 2010 Copyright Kevin Joseph McGown, 2010 All rights reserved. The dissertation of Kevin Joseph McGown is ap- proved, and it is acceptable in quality and form for publication on microfilm and electronically: Chair University of California, San Diego 2010 iii DEDICATION To my wife iv TABLE OF CONTENTS Signature Page . iii Dedication . iv Table of Contents . v List of Tables . vii Acknowledgements . viii Vita . ix Abstract of the Dissertation . x 1 Introduction . 1 1.1 First Notions . 1 1.2 History . 2 1.3 Open Problems . 4 1.4 Main Results . 5 2 Preliminaries . 11 2.1 Algebraic Number Fields . 11 2.2 Dirichlet Characters . 13 2.3 Residue Symbols in Number Fields . 15 2.4 Class Field Theory . 15 2.5 Zeta Functions and L-Functions . 17 2.6 Number Fields with Class Number One . 19 2.7 Heilbronn's Criterion . 21 3 Norm-Euclidean Galois Fields . 22 3.1 Conditions for the Failure of the Euclidean Property . 22 3.2 An Algorithm and Some Computations .
    [Show full text]
  • Some Aspects and Applications of the Riemann Hypothesis Over Finite Fields
    SOME ASPECTS AND APPLICATIONS OF THE RIEMANN HYPOTHESIS OVER FINITE FIELDS E. KOWALSKI Abstract. We give a survey of some aspects of the Riemann Hypothe- sis over finite fields, as it was proved by Deligne, and its applications to analytic number theory. In particular, we concentrate on the formalism leading to Deligne's Equidistribution Theorem. 1. Introduction The goal of this survey is to present some aspects of the Riemann Hy- pothesis over finite fields. The context is Deligne's celebrated work ([5], [6]) and its applications, and the text is roughly split in two parts. In the first part, we try to introduce and motivate the framework in which the powerful formalism of ´etalecohomology and the Riemann Hypothesis operate, em- phasizing aspects leading to Deligne's remarkable Equidistribution Theorem. The second part (starting in Section 5) is a discussion of this theorem, which involves naturally \families" of exponential sums and L-functions over finite fields, and of some (mostly) recent applications of the Riemann Hypoth- esis and Deligne's theorem, concluding with a short list of open problems (emphasizing general, \philosophical" issues, rather than specific questions). This is written with a target audience of readers who are not experts in algebraic geometry, in particular analytic number theorists. We use a few basic examples as references, notably Gauss sums, Kloosterman sums (and their average Sato-Tate distribution) and the very simple { but enlighten- ing { case of finite (zero-dimensional) algebraic varieties. The emphasis is throughout in situations which, at least at first sight, are not immediately or obviously analogue to the classical Riemann Hypothesis for the Riemann zeta and Dirichlet L-functions.
    [Show full text]
  • Zetapack: a System for the Computation of Zeta and L-Functions with Mathematica
    ZetaPack: A system for the computation of zeta and L-functions with Mathematica Kevin A. Broughan Version: 6th July 2007 2 Contents Contents 3 0.1 Preface . 9 0.2 Description . 9 0.3 Installation . 9 0.4 Acknowledgements . 10 0.5 Dedication . 10 1 Zeta and L-functions 11 1.1 Introduction . 11 1.2 Classes of zeta and L-functions . 12 1.2.1 The Selberg class . 12 1.2.2 Properties of the Selberg Class . 13 1.2.3 Selberg's conjectures . 14 1.2.4 Consequences of the Selberg de nitions and conjectures . 15 1.2.5 Functions in the Selberg class . 15 1.2.6 Dokchitser L-functions . 15 1.2.7 Functions in the Dokchitser class . 16 1.3 Automorphic forms for GL(n; R) ............................. 16 1.3.1 Iwasawa decomposition . 16 1.3.2 Algebras of di erential operators . 17 1.3.3 The power function . 17 1.3.4 Maass forms . 18 1.3.5 Fourier expansions . 18 1.3.6 Jacquet's Whittaker function . 19 1.3.7 Hecke operators . 20 1.3.8 Godement-Jacquet L-function . 21 1.3.9 Functional equation . 22 1.4 Dictionaries . 23 1.5 ZetaPack functions . 23 1.6 The L-function data type . 24 2 A database of elementary Dirichlet Series 27 2.1 Introduction . 27 2.2 Multiplicative Functions . 27 3 4 CONTENTS 2.3 Database summary . 29 2.4 Operations on Dirichlet series . 31 2.5 Inverting a Riemann zeta related Dirichlet series . 32 2.6 Euler Products . 33 2.7 Evaluating the Riemann zeta function .
    [Show full text]
  • Analytic Number Theory
    http://dx.doi.org/10.1090/pspum/024 Volume 24 Analytic Number Theory Symposium on Analytic Number Theory March 27-30, 1972 St. Louis, Missouri Harold G. Diamond Editor Analyti c Numbe r Theor y Proceedings of Symposia in PURE MATHEMATICS Volume 24 Analytic Number Theory Symposium on Analytic Number Theory March 27-30, 1972 St. Louis, Missouri Harold G. Diamond Editor - American Mathematical Society $ Providence, Rhode Island PROCEEDINGS OF THE SYMPOSIUM IN PURE MATHEMATICS OF THE AMERICAN MATHEMATICAL SOCIETY HELD AT THE ST. LOUIS UNIVERSITY ST. LOUIS, MISSOURI MARCH 27-30, 1972 Prepared by the American Mathematical Society under National Science Foundation Grant GP-32302 2000 Mathematics Subject Classification. Primary 11-02. Library of Congress Cataloging-in-Publication Data Symposium in Pure Mathematics, St. Louis University 1972. Analytic number theory. (Proceedings of symposia in pure mathematics, v. 24) Includes bibliographies. 1. Numbers, Theory of— Congresses. I. Diamond, Harold G., 1940- ed. II. American Mathematical Society. III. Title. IV. Series. QA241.S88 1972 512'.73 ISBN 0-8218-1424-9 72-10198 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 a chapter 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. Republication, systematic copying, or multiple reproduction of any material in this publication is permitted only under license from the American Mathematical Society. Requests for such permission should be addressed to the Assistant to the Publisher, American Mathematical Society, P.
    [Show full text]
  • Math 229: Introduction to Analytic Number Theory Incomplete Character Sums I: the Davenport-Erd˝Osbound, and the Distribution of Short Character Sums
    Math 229: Introduction to Analytic Number Theory Incomplete character sums I: The Davenport-Erd˝osbound, and the distribution of short character sums Finally, we consider upper bounds on exponential sum involving a character, again concentrating on the simplest such sum N X Sχ(N) := χ(n). n=1 Here χ is a primitive character mod q > 1. We already encountered the P´olya- Vinogradov bound: 1/2 |Sχ(N)| q log q for all N. We motivate our further study of Sχ(N) with two paradigmatic applications. The first application concerns an analogue of Lindel¨of’s conjecture “in the q-direction”: fix s = σ + it with σ ∈ [1/2, 1], and ask how |L(s, χ)| can grow as we vary χ. (If σ < 1/2 then 1 − σ > 1/2, so we first estimate L(1 − s, χ) and then use the functional equation; if σ > 1 then the Dirich- let series converges, and |L(s, χ)| < ζ(σ) is an upper bound independent of χ.) R ∞ −1−s Partial summation gives L(s, χ) = s 1 y Sχ(y) dy. Thus for fixed s we R ∞ −1−σ have L(s, χ) 1 y |Sχ(y)| dy. Hence upper bounds on |Sχ(y)| directly yield upper bounds on L(s, χ). For instance, by combining the trivial estimate |Sχ(y)| ≤ y with the P´olya-Vinogradov bound we find Z q1/2 log q Z ∞ L(s, χ) y−σdy + q1/2 log q y−1−σdy (q1/2 log q)1−σ, 1 q1/2 log q except for σ = 1, for which we obtain L(s, χ) log q as we have already seen.
    [Show full text]
  • Book Pseudocode
    Appendix BOOK PSEUDOCODE All algorithms in this book are written in a particular pseudocode form describable, perhaps, as a "fusion of English and C languages." The motivations for our particular pseudocode design have been summarized in the Preface, where we have indicated our hope that this "mix" will enable all readers to understand, and programmers to code, the algorithms. Also in the Preface we indicated a network source for Mathematica implementations of the book algorithms. That having been said, the purpose of this Appendix is to provide not a rigorous compendium of instruction definitions, for that would require something like an entire treatise on syntactical rules as would be expected to appear in an off-the-shelf C reference. Instead, we give below some explicit examples of how certain pseudocode statements are to be interpreted. English, and comments For the more complicated mathematical manipulations within pseudocode, we elect for English description. Our basic technical motivation for allowing "English" pseudocode at certain junctures is evident in the following example. A statement in the C language if((n== floor(n» && (j == floor(sqrt(j»*floor(sqrt(j»» ... , which really means "if n is an integer and j is a square," we might have cast in this book as if(n, vJ E Z) ... That is, we have endeavored to put "chalkboard mathematics" within conditionals. We have also adopted a particular indentation paradigm. If we had allowed (which we have not) such English as: For all pseudoprimes in S, apply equation (X); Apply equation (Y); then, to the aspiring programmer, it might be ambiguous whether equation (Y) were to be applied for all pseudoprimes, or just once, after the loop on equation (X).
    [Show full text]
  • Character Sum Estimates in Finite Fields and Applications by Brandon
    Character Sum Estimates in Finite Fields and Applications by Brandon Hanson A thesis submitted in conformity with the requirements for the degree of Doctor of Philosophy Graduate Department of Mathematics University of Toronto c Copyright 2015 by Brandon Hanson Abstract Character Sum Estimates in Finite Fields and Applications Brandon Hanson Doctor of Philosophy Graduate Department of Mathematics University of Toronto 2015 In this thesis we present a number of character sum estimates for sums of various types occurring in finite fields. The sums in question generally have an arithmetic combinatorial flavour and we give applications of such estimates to problems in arithmetic combinatorics and analytic number theory. Conversely, we demonstrate ways in which the theory of arithmetic combinatorics can be used to obtain certain character sum estimates. ii Dedication To my friends, for all the laughs. To my family, for their support. To my teachers, for inspiring me. To John, for his patience and commitment. To Michelle, for everything. iii Acknowledgements First and foremost I must thank John Friedlander, my thesis advisor, for giving me so much of his time and patience. This thesis would not have been possible without all of the helpful discussions we had. I also want to thank Leo Goldmakher for getting me interested in the field and providing much encouragement along the way. Thanks to Kumar Murty and Antal Balog for being a part of my thesis committee and providing fruitful discussion. Finally, like every graduate student in math at the University of Toronto, I am indebted to Ida Bulat and Jemima Merisca. They made my life in the graduate program so much easier.
    [Show full text]
  • The Distribution of Quadratic Residues and Non-Residues in the Goldwasser–Micali Type of Cryptosystem
    J. Math. Cryptol. 8 (2014), 115–140 DOI 10.1515/jmc-2013-0001 © de Gruyter 2014 The distribution of quadratic residues and non-residues in the Goldwasser–Micali type of cryptosystem Benjamin Justus Communicated by Spyros Magliveras Abstract. We provide unconditional results and conditional ones under the assumption of GRH (Generalized Riemann Hypothesis) on the distribution of quadratic residues and quadratic non-residues in Z=N Z, where N pq is an RSA modulus used in the Gold- wasser–Micali cryptosystem. The paper alsoD discusses cryptographic implications of the results obtained. Keywords. Quadratic residuosity problem, Goldwasser–Micali cryptosystem, quadratic residues distribution. 2010 Mathematics Subject Classification. 94A60, 11A15. 1 Introduction Goldwasser and Micali in [6] introduced the concept of probabilistic encryption. In the same paper, they proved that their probabilistic public-key encryption scheme is secure based on the hardness of the quadratic residuosity problem. Given a composite integer N , and a positive integer a relative prime to N , the quadratic residuosity problem is to decide whether a is a quadratic residue or a quadratic non-residue modulo N (i.e. whether or not x2 a mod N has a solu- D tion). The modulus N in the Goldwasser–Micali cryptosystem is a typical RSA modulus used in the RSA cryptosystem. That is, N pq for odd distinct primes D p; q about the same size. The quadratic residuosity problem is known to be com- putationally hard if the factorization of N is not known, see Section 2. The prob- lem currently does not admit polynomial time solutions, and is listed as an open problem [1].
    [Show full text]
  • Character Sums and Arithmetic Combinatorics
    Character sums and arithmetic combinatorics Mei-Chu Chang Abstract In this survey we review some old and new results on character sums and their applications to various problems in analytic number theory, e.g., smallest quadratic nonresidues, Dirichlet L-function, Linnik’s problem. We also discuss open problems in this area. Some of the techniques involved belong to arithmetic combinatorics. One may hope for these methods to lead to further progress. Keywords Character sums • Zero-free regions. Mathematics Subject Classification (2010): 11L40, 11M06. A function W Z=qZ !fz 2 C WjzjD1g[f0g is a multiplicative character mod q if it satisfies the properties that .mn/ D .m/.n/, and .n/ D 0 if gcd.n; q/ 6D 1: We are interested in bounding non-trivially the character sum of over an interval of length H Ä q. More precisely, we want to study the following problem. Problem 1. Assuming is non-principal and q 0, how small H D H.q/ can be such that ˇ C ˇ ˇ aXH ˇ ˇ .n/ˇ < H1 ‹ (1) nDaC1 In 1918, Polya and Vinogradov (Theorem 12.5 in [27]) had the estimate for p H q log q. Theorem 1 (Polya-Vinogradov). Let be a non-principal Dirichlet character mod q. Then ˇ aXCH ˇ ˇ ˇ 1 ˇ .m/ˇ < Cq 2 .log q/: mDaC1 M.-C. Chang () Department of Mathematics, University of California, Riverside, CA 92521, USA e-mail: [email protected] © Springer International Publishing Switzerland 2016 405 A. Beveridge et al. (eds.), Recent Trends in Combinatorics, The IMA Volumes in Mathematics and its Applications 159, DOI 10.1007/978-3-319-24298-9_17 406 M.-C.
    [Show full text]
  • International Congress of Mathematicians
    International Congress of Mathematicians Hyderabad, August 19–27, 2010 Abstracts Short Communications Posters Editor Rajendra Bhatia Co-Editors Arup Pal G. Rangarajan V. Srinivas M. Vanninathan Technical Editor Pablo Gastesi Contents Section 1: Logic and Foundations ....................... .............. 1 Section 2: Algebra................................... ................. 10 Section 3: Number Theory.............................. .............. 71 Section 4: Algebraic and Complex Geometry............... ........... 106 Section 5: Geometry.................................. ................ 116 Section 6: Topology.................................. ................. 150 Section 7: Lie Theory and Generalizations............... .............. 177 Section 8: Analysis.................................. .................. 188 Section 9: Functional Analysis and Applications......... .............. 254 Section 10: Dynamical Systems and Ordinary Differential Equations . 287 Section 11: Partial Differential Equations.............. ................. 338 Section 12: Mathematical Physics ...................... ................ 375 Section 13: Probability and Statistics................. .................. 431 Section 14: Combinatorics............................ .................. 460 Section 15: Mathematical Aspects of Computer Science..... ............ 509 Section 16: Numerical Analysis and Scientific Computing... ............ 533 Section 17: Control Theory and Optimization ............. ............. 556 Section 18: Mathematics in Science and Technology
    [Show full text]
  • Annual Progress Report on the Mathematical Sciences Research Institute 2008-2009 Activities Supported by NSF Grant DMS – 0441170 May 1, 2010
    Annual Progress Report on the Mathematical Sciences Research Institute 2008-2009 Activities supported by NSF Grant DMS – 0441170 May 1, 2010 Mathematical Sciences Research Institute Annual Report for 2008-2009 1. Overview of Activities...........................................................................................................3 1.1 New Developments ......................................................................................................3 1.2 Summary of Demographic Data ..................................................................................7 1.3 Major Programs & Associated Workshops...................................................................9 1.4 Scientific Activities Directed at Underrepresented Groups in Mathematics..............19 1.5 Summer Graduate Workshops ....................................................................................20 1.6 Other Scientific Workshops ………………………………………………………...22 1.7 Educational & Outreach Activities .............................................................................24 1.8 Programs Consultant List ...........................................................................................27 2. Program and Workshop Participation ...........................................................................28 2.1 Program Participant List .............................................................................................28 2.2 Program Participant Summary....................................................................................35
    [Show full text]