Zeta Functions, One–Way Functions, and Pseudorandom Number Generators

Total Page:16

File Type:pdf, Size:1020Kb

Zeta Functions, One–Way Functions, and Pseudorandom Number Generators ZETA FUNCTIONS, ONE{WAY FUNCTIONS, AND PSEUDORANDOM NUMBER GENERATORS Michael Anshel Department of Computer Sciences, City College of New York, New York, NY 10031 Dorian Goldfeld Department of Mathematics, Columbia University New York, NY 10027 Abstract. New candidate one{way functions which arise from the intractable problem of determining a zeta function from its initial Dirichlet coefficients are presented. This in- tractable problem appears to be totally unrelated to the well known intractable problems of integer factorization and the computation of discrete logarithms. We introduce the feasible Selberg class of zeta functions and focus on three special subclasses: ZKronecker = Dirich- let L-functions with real characters, ZElliptic = L{functions of elliptic curves, and ZArtin = Artin L-functions. It is shown that the reduction (mod 2) map on the Dirichlet coefficients of ZElliptic induces a map ZElliptic !ZArtin. The assumption that it is not feasible (in polyno- mial time) to determine an Artin L{function from its initial Dirichlet coefficients leads to a new pseudorandom number generator. These results are interpreted in various cryptographic settings by employing the Eisenstein{Jacobi law of cubic reciprocity. Key Words: Zeta function, One{way function, Pseudorandom number generator, Elliptic curve, Frobenius element, Cubic reciprocity law, Feasible Selberg class. x1. Introduction: A central problem in cryptography is to establish the existence of one{way functions. Such a function would have the property that while it is computable in polynomial time, its inverse is not. One approach to this problem is to construct candidate one{way functions from seemingly intractable problems in number theory. We introduce a new intractable problem arising from the theory of zeta functions which leads to a new class of one{way functions based on the arithmetic theory of zeta functions. Moreover, there appears to be no relation between this problem and other intractable problems such as integer factor- ization and the computation of discrete logarithms where known attacks have emerged in recent years (see [22, 26]). At present the authors are unaware of any methods at all that would provide an attack on our candidate one{way functions. Typeset by AMS-TEX 1 It is a consequence of the main theorem of [12] that a 1{1 one{way function implies the existence of a pseudorandom number generator. The construction of such pseudoran- dom number generators, however, is computationally intensive. In our case we explicitly construct from a given elliptic curve a pseudorandom number generator PNGElliptic which can be computed very efficiently and at low computational cost. Under the assumption that two different classes of zeta functions (the elliptic class and the Artin class, to be defined below) give rise to one{way functions, we prove that an elliptic curve satisfying certain hypotheses implies the existence of such a pseudorandom number generator. In this regard, the second author would like to take this opportunity to thank Fred Diamond for many helpful discussions concerning `{adic representations. x2. One{way Functions and the Feasible Selberg Class Let n ≥ 0 be an integer and define blog2 nc + 1; if n > 0 d2(n) = 1; if n = 0: where for an arbitrary real number x ≥ 0, bxc denotes the greatest integer less than or equal to x. We refer to d2(n) as the bit size of n. We extend this notion to non{negative t integral vectors by defining the norm jj(n1; n2; : : : ; nt)jj of a vector (n1; n2; : : : ; nt) 2 N as t X jj(n1; n2; : : : ; nt)jj = d2(ni): i=1 Fix positive rational integers r; s. A function r s f : N −! N is a one{way function provided the following three conditions hold. (2.1) There exists an integer k > 0 such that 1 k jj~njj k ≤ jjf(~n)jj ≤ jj~njj r for ~n = (n1; n2; : : : ; nr) 2 N : (2.2) f(~n) can be computed in polynomial time in jj~njj: (2.3) Given m 2 Ns, there does not exist a polynomial time algorithm which either computes a vector ~n 2 Nr such that f(~n) = ~m or indicates that no such value exists. Condition (2.1) says that f(~n) is neither polynomially longer or shorter than ~n. Cur- rently, there is no guarantee that one{way functions exist even if P 6= NP . Certain can- didate one{way functions associated with factorization, exponentiation modulo a prime, and discrete logarithms, etc. have been proposed. We introduce new candidate one{way functions based on a seemingly intractable problem in the theory of zeta functions. Our 2 candidate one{way functions arise from a very general class of zeta functions, the feasible Selberg class, which we now define. In order to specify our intractable problem we axiomatically define a class, Z, of zeta functions; the feasible Selberg class (defined from [23]). Every zeta function Z(s) 2 Z is given by a Dirichlet series 1 X a(n) Z(s) = ; a(n) 2 ns C n=1 which is absolutely convergent in some half-plane Re(s) 1: We further assume that Z(s) is a meromorphic function of a single complex variable s which satisfies the following hypotheses: (2.4) a(n) = O(nC ) for some constant C > 0 independent of n. P −s r (2.5) log Z(s) = n b(n) · n , where b(n) = 0 unless n = p , a positive prime power. (2.6) Given a prime power pr, 9 an algorithm to compute b(pr) in polynomial time. (2.7) There exist A; k; bi > 0; w 2 C with jwj = 1, and a polynomial P (s) such that Z(s) satisfies a functional equation of type: ! s Y Λ(s) = A P (s) Γ(bis + di) Z(s) = w · Λ(k − s¯): i Selberg [23] introduced the class of zeta functions (now called the Selberg class) satisfy- ing (2.4), (2.5), (2.7). The axiom (2.6) is new and justifies the term feasible Selberg class. It is precisely the axiom (2.6) which makes this class so interesting for cryptography. Note that axiom (2.6) is quite restrictive; zeta functions with transcendental coefficients cannot be in the feasible Selberg class. The constant A in the functional equation is called the conductor of the zeta function. The Riemann hypothesis for any subfamily Z0 ⊂ Z is the statement that all zeros of Λ(s) (corresponding to Z(s) 2 Z0) have Re(s) = k=2: There are numerous well known special subfamilies of Z: These include, Dedekind zeta functions of number fields [15] (among which is the famous Riemann zeta function), Dirich- let L-functions [8], and zeta functions associated to modular forms [20]. In contrast, the Hasse{Weil zeta function for algebraic varieties over a finite field may not satisfy axiom (2.6) (see [10]). Definition: We say a subfamily Z0 of Z is abundant provided: for every > 0; the number of distinct zeta functions in the subfamily for which the conductor A lies in an interval of length B is greater than B1− as B ! 1: With this definition, we introduce the motivating problem for this paper: 3 0 Problem[1]: Let Z be a fixed abundant subfamily of Z: Given a list fα1; α2; : : : ; αkg of complex numbers, how difficult is it to determine whether or not there exists 1 X Z(s) = a(n) · n−s 2 Z0 n=1 such that a(n) = αn for n = 1; 2; : : : k, and the conductor of Z(s) lies in a given bounded interval. If such a zeta function exists, how difficult is it to construct one such zeta func- tion? The most general class of zeta functions which satisfy (2.4), (2.5), (2.6), (2.7), and for which there is a comprehensive arithmetic theory is the class of L-functions associated to automorphic representations of reductive groups in the sense of Jacquet{Langlands (see [14], [3]). We conjecture that problem[1] is intractable for abundant subfamilies of Z consisting of L{functions associated to cuspidal automorphic representations of reductive groups, and that this intractable problem provides the basis for constructing new one{ way functions. As evidence for this conjecture, we will focus on three specific subclasses, ZKronecker; ZElliptic and ZArtin. x3. The classes ZKronecker; ZElliptic and ZArtin We define ZKronecker [8] to be the class of all Dirichlet L-series of the form 1 X d L (s) = · n−s; d n n=1 d where n denotes the Kronecker symbol and d is any product of relatively prime factors of the form 1 (p−1) −4; 8; −8; (−1) 2 p (p a positive odd prime): Such integers d are called fundamental discriminants. A simple example of Problem[1] is the following: Problem[2]: Let B denote a large number. Set b = (log(B))κ where κ > 2: Suppose we are given a list f1; 2; : : : ; bg where each j = ±1 for j = 1; 2; : : : ; b: How difficult is it d to decide if an L{function, Ld(s) 2 ZKronecker, with B ≤ jdj ≤ 2B, satisfies n = n for n = 1; 2; : : : ; b? If such Ld(s) exists, how difficult is it to construct one such fundamental discriminant d? Remarks: If we assume the Riemann hypothesis for the class ZKronecker then it can be shown (see [11]) there will be at most one such d: Problem[2] was first stated by Damg˚ard [7] who was the first to suggest that the genuine hardness of this problem could be directly used to construct a cryptographically strong bit generator. We now define the class ZElliptic: An elliptic curve E over Q is specified by a pair of 3 2 elements a; b 2 Q for which the discriminant ∆E = 4a + 27b 6= 0.
Recommended publications
  • Selberg's Orthogonality Conjecture and Symmetric
    SELBERG'S ORTHOGONALITY CONJECTURE AND SYMMETRIC POWER L-FUNCTIONS PENG-JIE WONG Abstract. Let π be a cuspidal representation of GL2pAQq defined by a non-CM holomorphic newform of weight k ¥ 2. Let K{Q be a totally real Galois extension with Galois group G, and let χ be an irreducible character of G. In this article, we show that Selberg's orthogonality conjecture implies that the symmetric power L-functions Lps; Symm πq are primitive functions in the Selberg class. Moreover, assuming the automorphy for Symm π, we show that Selberg's orthogonality conjecture implies that each Lps; Symm π ˆ χq is automorphic. The key new idea is to apply the work of Barnet-Lamb, Geraghty, Harris, and Taylor on the potential automorphy of Symm π. 1. Introduction Thirty years ago, Selberg [21] introduced a class S of L-functions, called the Selberg class nowadays. The class S consists of functions F psq of a complex variable s enjoying the following properties: (Dirichlet series and Euler product). For Repsq ¡ 1, 8 a pnq 8 F psq “ F “ exp b ppkq{pks ns F n“1 p k“1 ¸ ¹ ´ ¸ ¯ k kθ 1 with aF p1q “ 1 and bF pp q “ Opp q for some θ ă 2 , where the product is over rational primes p. Moreover, both Dirichlet series and Euler product of F converge absolutely on Repsq ¡ 1. (Analytic continuation and functional equation). There is a non-negative integer mF such that ps ´ 1qmF F psq extends to an entire function of finite order. Moreover, there are numbers rF , QF ¡ 0, αF pjq ¡ 0, RepγF pjqq ¥ 0, so that rF s ΛF psq “ QF ΓpαF pjqs ` γF pjqqF psq j“1 ¹ satisfies ΛF psq “ wF ΛF p1 ´ sq for some complex number wF of absolute value 1.
    [Show full text]
  • Analytic Theory of L-Functions: Explicit Formulae, Gaps Between Zeros and Generative Computational Methods
    Zurich Open Repository and Archive University of Zurich Main Library Strickhofstrasse 39 CH-8057 Zurich www.zora.uzh.ch Year: 2016 Analytic theory of L-functions: explicit formulae, gaps between zeros and generative computational methods Kühn, Patrick Posted at the Zurich Open Repository and Archive, University of Zurich ZORA URL: https://doi.org/10.5167/uzh-126347 Dissertation Published Version Originally published at: Kühn, Patrick. Analytic theory of L-functions: explicit formulae, gaps between zeros and generative computational methods. 2016, University of Zurich, Faculty of Science. UNIVERSITÄT ZÜRICH Analytic Theory of L-Functions: Explicit Formulae, Gaps Between Zeros and Generative Computational Methods Dissertation zur Erlangung der naturwissenschaftlichen Doktorwürde (Dr. sc. nat.) vorgelegt der Mathematisch-naturwissenschaftlichen Fakultät der Universität Zürich von Patrick KÜHN von Mendrisio (TI) Promotionskomitee: Prof. Dr. Paul-Olivier DEHAYE (Vorsitz und Leitung) Prof. Dr. Ashkan NIKEGHBALI Prof. Dr. Andrew KRESCH Zürich, 2016 Declaration of Authorship I, Patrick KÜHN, declare that this thesis titled, ’Analytic Theory of L-Functions: Explicit Formulae, Gaps Between Zeros and Generative Computational Methods’ and the work presented in it are my own. I confirm that: This work was done wholly or mainly while in candidature for a research degree • at this University. Where any part of this thesis has previously been submitted for a degree or any • other qualification at this University or any other institution, this has been clearly stated. Where I have consulted the published work of others, this is always clearly at- • tributed. Where I have quoted from the work of others, the source is always given. With • the exception of such quotations, this thesis is entirely my own work.
    [Show full text]
  • Seminar on Potential Modularity and Its Applications
    Seminar on Potential Modularity and its Applications Panagiotis Tsaknias April 1, 2011 1 Intro A main theme of modern (algebraic) number theory is the study of the absolute Galois group GQ of Q and more specifically its representations. Although one dimensional Galois representations admit an elegant description through class field theory, the general case is nowhere near that easy to handle. The well known Langlands Program is a far reaching web of conjectures that was devised in effort to describe such representations. On one side one has analytic objects (automorphic representations) whose behavior is\better understood", i.e. the L-function associated with them admits an analytic continuation to the whole complex plane and satisfies a functional equation. On the other side, one has L-series that come from Galois representations and whose analytic continuation and functional equation is difficult to show. The Langlands program suggests that one can indirectly prove that by showing that the Galois representation in question is associated with an automorphic representation, i.e. they are associated with the same L-function. One of the first examples of this approach was the classical proof that CM elliptic curves are modular, and therefore their L-function admits an analytic continuation and satisfies a functional equation. For more general classes of elliptic curves the first major break through was done by Wiles [22] and Taylor-Wiles [19] who proved that all semisimple elliptic curves are modular. Subsequent efforts culminating with the work done by Breuil-Conrad-Diamond-Taylor [2] finally proved modularity for all elliptic curves over Q.
    [Show full text]
  • Henri Darmon
    Henri Darmon Address: Dept of Math, McGill University, Burnside Hall, Montreal, PQ. E-mail: [email protected] Web Page: http://www.math.mcgill.ca/darmon Telephone: Work (514) 398-2263 Home: (514) 481-0174 Born: Oct. 22, 1965, in Paris, France. Citizenship: Canadian, French, and Swiss. Education: 1987. B.Sc. Mathematics and Computer Science, McGill University. 1991. Ph.D. Mathematics, Harvard University. Thesis: Refined class number formulas for derivatives of L-series. University Positions: 1991-1994. Princeton University, Instructor. 1994-1996. Princeton University, Assistant Professor. 1994-1997. McGill University, Assistant Professor. 1997-2000. McGill University, Associate Professor. 2000- . McGill University, Professor. 2005-2019. James McGill Professor, McGill University. Other positions: 1991-1994. Cercheur hors Qu´ebec, CICMA. 1994- . Chercheur Universitaire, CICMA. 1998- . Director, CICMA (Centre Interuniversitaire en Calcul Math´ematique Alg´ebrique). 1999- . Member, CRM (Centre de Recherches Math´ematiques). 2005-2014. External member, European network in Arithmetic Geometry. Visiting Positions: 1991. IHES, Paris. 1995. Universit´a di Pavia. 1996. Visiting member, MSRI, Berkeley. 1996. Visiting professor and guest lecturer, University of Barcelona. 1997. Visiting Professor, Universit´e Paris VI (Jussieu). 1997. Visitor, Institut Henri Poincar´e. 1998. Visiting Professor and NachDiplom lecturer, ETH, Zuric¨ h. 1999. Visiting professor, Universit`a di Pavia. 2001. Visiting professor, Universit`a di Padova. 2001. Korea Institute for Advanced Study. 2002. Visiting professor, RIMS and Saga University (Japan). 1 2003. Visiting Professor, Universit´e Paris VI, Paris. 2003. Visiting professor, Princeton University. 2004. Visiting Professor, Universit´e Paris VI, Paris. 2006. Visiting Professor, CRM, Barcelona, Spain. 2008. Visiting Professor, Universit´e Paris-Sud (Orsay).
    [Show full text]
  • On the Selberg Class of L-Functions
    ON THE SELBERG CLASS OF L-FUNCTIONS ANUP B. DIXIT Abstract. The Selberg class of L-functions, S, introduced by A. Selberg in 1989, has been extensively studied in the past few decades. In this article, we give an overview of the structure of this class followed by a survey on Selberg's conjectures and the value distribution theory of elements in S. We also discuss a larger class of L-functions containing S, namely the Lindel¨ofclass, introduced by V. K. Murty. The Lindel¨ofclass forms a ring and its value distribution theory surprisingly resembles that of the Selberg class. 1. Introduction The most basic example of an L-function is the Riemann zeta-function, which was intro- duced by B. Riemann in 1859 as a function of one complex variable. It is defined on R s 1 as ∞ 1 ( ) > ζ s : s n=1 n It can be meromorphically continued to( the) ∶= wholeQ complex plane C with a pole at s 1 with residue 1. The unique factorization of natural numbers into primes leads to another representation of ζ s on R s 1, namely the Euler product = −1 1 ( ) ( ) > ζ s 1 : s p prime p The study of zeta-function is vital to( ) understanding= M − the distribution of prime numbers. For instance, the prime number theorem is a consequence of ζ s having a simple pole at s 1 and being non-zero on the vertical line R s 1. ( ) = In pursuing the analogous study of distribution( ) = of primes in an arithmetic progression, we consider the Dirichlet L-function, ∞ χ n L s; χ ; s n=1 n ( ) for R s 1, where χ is a Dirichlet character( ) ∶= moduloQ q, defined as a group homomorphism ∗ ∗ χ Z qZ C extended to χ Z C by periodicity and setting χ n 0 if n; q 1.
    [Show full text]
  • A First Course in Modular Forms
    springer.com Mathematics : Number Theory Diamond, Fred, Shurman, Jerry A First Course in Modular Forms Covers many topics not covered in other texts on elliptic curves This book introduces the theory of modular forms with an eye toward the Modularity Theorem: All rational elliptic curves arise from modular forms. The topics covered include • elliptic curves as complex tori and as algebraic curves, • modular curves as Riemann surfaces and as algebraic curves, • Hecke operators and Atkin–Lehner theory, • Hecke eigenforms and their arithmetic properties, • the Jacobians of modular curves and the Abelian varieties associated to Hecke eigenforms, • elliptic and modular curves modulo p and the Eichler–Shimura Relation, • the Galois representations associated to elliptic curves and to Hecke eigenforms. As it presents these ideas, the book states the Modularity Theorem in various forms, relating them to each other and touching on their applications to number theory. A First Course in Modular Forms is Springer written for beginning graduate students and advanced undergraduates. It does not require 2005, XVI, 450 p. 57 illus. background in algebraic number theory or algebraic geometry, and it contains exercises 1st throughout. Fred Diamond received his Ph.D from Princeton University in 1988 under the edition direction of Andrew Wiles and now teaches at King's College London. Jerry Shurman received his Ph.D from Princeton University in 1988 under the direction of Goro Shimura and now teaches at Reed College. Printed book Hardcover Order online at
    [Show full text]
  • Modularity of Some Potentially Barsotti-Tate Galois Representations
    Modularity of some potentially Barsotti-Tate Galois representations A thesis presented by David Lawrence Savitt to The Department of Mathematics in partial ful¯llment of the requirements for the degree of Doctor of Philosophy in the subject of Mathematics Harvard University Cambridge, Massachusetts May 2001 °c 2001 - David Savitt All rights reserved. iii Thesis advisor Author Richard Lawrence Taylor David Lawrence Savitt Modularity of some potentially Barsotti-Tate Galois representations Abstract We prove a portion of a conjecture of Conrad-Diamond-Taylor, which yields proofs of some 2-dimensional cases of the Fontaine-Mazur conjectures. Let ½ be a continuous odd irreducible l-adic Galois representation (l an odd prime) satisfying the hypotheses of the Fontaine-Mazur conjecture and such that ½ is modular. The notable additional hypotheses we must impose in order to conclude that ½ is mod- ular are that ½ is potentially Barsotti-Tate, that the Weil-Deligne representation associated to ½ is irreducible and tamely rami¯ed, and that ½ is conjugate to a representation over Fl which is reducible with scalar centralizer. The proof follows techniques of Breuil, Conrad, Diamond, and Taylor, and in particular requires extensive calculation with Breuil's classi¯cation of l-torsion ¯nite flat group schemes over base schemes with high rami¯cation. iv Contents 1. Introduction 1 1.1. Aims, results, and strategies 1 1.2. Background 4 1.3. Open questions and progress 17 2. Main Results 22 3. Deformation Theory 25 3.1. Dieudonn¶emodule calculations 26 3.2. Deformation problems 29 3.3. Strategy of the calculation 32 4. Review of Breuil Modules with Descent Data 33 5.
    [Show full text]
  • Arxiv:1711.06671V1 [Math.NT] 17 Nov 2017 Function Enetnieysuid[1 Nrcn Ie.Tesuyo Au Dist Value of Study the of Times
    VALUE DISTRIBUTION OF L-FUNCTIONS ANUP B. DIXIT Abstract. In 2002, V. Kumar Murty [8] introduced a class of L-functions, namely the Lindel¨of class, which has a ring structure attached to it. In this paper, we establish some results on the value distribution of L-functions in this class. As a corollary, we also prove a uniqueness theorem in the Selberg class. 1. Introduction In 1992, Selberg [10] formulated a class of L-functions, which can be regarded as a model for L-functions originating from arithmetic objects. The value distribution of such L-functions has been extensively studied [11] in recent times. The study of value distribution is concerned with the zeroes of L-functions and more generally, with the set of pre-images L−1(c) := {s ∈ C : L(s)= c} where c is any complex number, which Selberg called the c-values of L. For any two meromorphic functions f and g, we say that they share a value c ignoring multiplicity(IM) if f −1(c) is the same as g−1(c) as sets. We further say that f and g share a value c counting multiplicity(CM) if the zeroes of f(x) − c and g(x) − c are the same with multiplicity. The famous Nevanlinna theory [9] establishes that any two meromorphic functions of finite order sharing five values IM must be the same. Moreover, if they share four values CM, then one must be a M¨obius transform of the other. The numbers four and five are the best possible for meromorphic functions.
    [Show full text]
  • Uncoveringanew L-Function Andrew R
    UncoveringaNew L-function Andrew R. Booker n March of this year, my student, Ce Bian, plane, with the exception of a simple pole at s = 1. announced the computation of some “degree Moreover, it satisfies a “functional equation”: If 1 3 transcendental L-functions” at a workshop −s=2 γ(s) = ÐR(s) := π Ð (s=2) and Λ(s) = γ(s)ζ(s) at the American Institute of Mathematics (AIM). This article aims to explain some of the then I (1) (s) = (1 − s). motivation behind the workshop and why Bian’s Λ Λ computations are striking. I begin with a brief By manipulating the ζ-function using the tools of background on L-functions and their applications; complex analysis (some of which were discovered for a more thorough introduction, see the survey in the process), one can deduce the famous Prime article by Iwaniec and Sarnak [2]. Number Theorem, that there are asymptotically x ≤ ! 1 about log x primes p x as x . L-functions and the Selberg Class Other L-functions reveal more subtle properties. There are many objects that go by the name of For instance, inserting a multiplicative character L-function, and it is difficult to pin down exactly χ : (Z=qZ)× ! C in the definition of the ζ-function, what one is. In one of his last published papers we get the so-called Dirichlet L-functions, [5], the late Fields medalist A. Selberg tried an Y 1 L(s; χ) = : axiomatic approach, basically by writing down the 1 − χ(p)p−s common properties of the known examples.
    [Show full text]
  • Arxiv:1904.03123V2 [Math.NT] 30 Oct 2019 N Any and J Uhta Nteregion the in That Such Then Hoe 1.1
    ZEROS OF THE EXTENDED SELBERG CLASS ZETA-FUNCTIONS AND OF THEIR DERIVATIVES RAMUNAS¯ GARUNKSTISˇ Abstract. Levinson and Montgomery proved that the Riemann zeta-function ζ(s) and its derivative have approximately the same number of non-real zeros left of the critical line. R. Spira showed that ζ′(1/2+ it) = 0 implies ζ(1/2+ it) = 0. Here we obtain that in small areas located to the left of the critical line and near it the functions ζ(s) and ζ′(s) have the same number of zeros. We prove our result for more general zeta-functions from the extended Selberg class S. We also consider zero trajectories of a certain family of zeta-functions from S. 1. Introduction Let s = σ + it. In this paper, T always tends to plus infinity. Speiser [17] showed that the Riemann hypothesis (RH) is equivalent to the absence of non-real zeros of the derivative of the Riemann zeta-function ζ(s) left of the critical line σ = 1/2. Later on, Levinson and Montgomery [11] obtained the quantitative version of the Speiser’s result: Theorem (Levinson-Montgomery) Let N −(T ) be the number of zeros of ζ(s) − ′ in R :0 < t < T, 0 <σ< 1/2. Let N1 (T ) be the number of zeros of ζ (s) in R. − Then N1 (T )= N(T )+ O(log T ). − Unless N (T ) > T/2 for all large T there exists a sequence Tj , Tj as j such that N −(T )= N −(T ). { } →∞ →∞ 1 j j arXiv:1904.03123v2 [math.NT] 30 Oct 2019 Here we prove the following theorem.
    [Show full text]
  • Distinct Zeros of Functions in the Selberg Class 1
    Distinct zeros of functions in the Selberg Class 1 K. Srinivas 1. Introduction. Selberg [S] defined a class of Dirichlet series that admit analytic continuation, functional equation and an Euler product. The proto- typical example of Selberg's class is the classical Riemann zeta function. In the same paper, Selberg formulated several fundamental conjectures. These conjectures have spectacular consequences ( see for example the paper by Murty [MR] and Kaczorowski and Perelli [KP] ). In this paper we study a question suggested by the properties of the Selberg class. More precisely, the Selberg class S ( see [S] ) is defined by the following axioms: P1 −s (i) ( Dirichlet series ) Every F 2 S is a Dirichlet series F (s) = n=1 a(n)n ; ( with s = σ + it) absolutely convergent for σ > 1: (ii) (Analytic continuation) There exists an integer m ≥ 0 such that (s − 1)mF (s) is an entire function of finite order . 1AMS classification 11M41 (11M26) (iii)( Functional equation ) F 2 S satisfies a functional equation of the type '(s) = w'(1 − s) where d s Y '(s) = Q Γ(λis + µi)F (s); i=1 here w is a complex number with absolute value 1, Q(> 0); λi(> 0); <µi(≥ 0) are certain contants. (iv) (Ramanujan Hypothesis ) For every > 0; a(n) = O(n): P1 −s (v) (Euler product) F 2 S satisfies log F (s) = n=1 b(n)n ; where m θ 1 b(n) = 0; unless n = p with m ≥ 1; and b(n) = O(n ) for some θ < 2 . Pd For F 2 S define deg F = 2 i=1 λi to be the degree of F .
    [Show full text]
  • Arxiv:1506.07630V2 [Math.NT] 31 Mar 2016 Itiuino H Eo N Ihidpnec Results
    SOME REMARKS ON THE CONVERGENCE OF THE DIRICHLET SERIES OF L-FUNCTIONS AND RELATED QUESTIONS J.KACZOROWSKI and A.PERELLI Abstract. First we show that the abscissae of uniform and absolute convergence of Dirichlet series coincide in the case of L-functions from the Selberg class S. We also study the latter abscissa inside the extended Selberg class, indicating a different behavior in the two classes. Next we address two questions about majorants of functions in S, showing links with the distribution of the zeros and with independence results. Mathematics Subject Classification (2000): 11M41, 30B50, 40A05, 42A75 Keywords: Dirichlet series, Selberg class, almost periodic functions 1. Introduction Let ∞ a(n) F (s)= ns n=1 be a Dirichlet series which converges somewhereX in the complex plane. It is well known that there are four classical abscissae associated with F (s): the abscissa of convergence σc(F ), of uniform convergence σu(F ), of absolute convergence σa(F ) and of boundedness σb(F ). It may well be that σc(F )= −∞, in which case the other three abscissae equal −∞ as well. From the theory of Dirichlet series we know that σc(F ) ≤ σb(F )= σu(F ) ≤ σa(F ), and in general this is best possible, i.e. inequalities cannot be replaced by equalities. We refer to Maurizi-Queff´elec [15] for a modern reference for this sort of problems. Our first result is that σb(F )= σa(F ) for an important class of Dirichlet series, namely those defining the L-functions of the Selberg class S. We recall that the axiomatic class S contains, at least conjecturally, most L-functions from number theory and automorphic forms theory, arXiv:1506.07630v2 [math.NT] 31 Mar 2016 and that σb(F )= σa(F ) is known in some special cases like the Riemann or the Dedekind zeta functions.
    [Show full text]