Numerical Calculation of Automorphic Functions for Finite Index Subgroups
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Farey Error Correcting Coding Text, Data and Images
International Journal of Applied Engineering Research ISSN 0973-4562 Volume 14, Number 9 (2019) pp. 2207-2211 © Research India Publications. http://www.ripublication.com Farey Error Correcting Coding Text, Data and Images Poornima M1 , S. Jagannathan2, R Chandrasekhar3, S.T. Kumara4 1 Mathematics Department , SJB Institute of Technology, Bangalore, Karnataka, India. 2 Computer Science & Engineering Department, Nagarjuna College of Engineering & Technology, Bangalore, Karnataka, India. 3 MCA Department, PESIT Research, Bangalore, Karnataka, India. 4 A P S College of Engineering, Bangalore, 560082, Karnataka, India. Abstract: 2. PRINCIPLES AND AXIOMS OF THE FAREY SEQUENCE A new scheme for encryption and decryption of plain text, data and the coding of medical images through Farey Farey Sequences for Farey1...Farey8 which are irreducible or Sequence is brought in the paper. It proposes the reduced simple decimal division quantities in [0, 1] for a given n is arithmetic point representations and more of integer and given below. whole number point implementations. The test case and Farey1 = [ 0/1, 1/1 ] outcomes are explained in the section 4 and 5. Farey2 = [ 0/1, ½, 1/1 ] Keywords: Error correcting codes, image coding, reduced arithmetic floating point, fixed point, digital signal Farey3 = [ 0/1, 1/3, ½, 2/3, 1/1 ] processing and farey sequences Farey4 = [0/1, ¼, 1/3, ½, 2/3, ¾, 1/1] Farey5 = [ 0/1,1/5 ,1/4, 1/3, 2/5, 1/2 ,3/5, 2/3, 4/5, 1/1] 1. INTRODUCTION The efficacy of Farey sequence applications for error correcting codes and image processing are brings out in the Farey6 = [ 0/1, 1/6,/5, ¼, 1/3, 2/5, ½, 3/5, 2/3, ¾, 4/5, paper. -
Multidimensional Farey Partitions by Arnaldo Nogueira a and Bruno
Indag. Mathem., N.S., 17 (3), 437-456 September 25, 2006 Multidimensional Farey partitions by Arnaldo Nogueira a and Bruno Sevennec b a Institut de Math~matiques de Luminy, 163, avenue de Luminy, 13288 Marseille, Cedex 9, France b Unit~ de MathOmatiques Pures etAppliquOes, Ecole Normale Sup&ieure de Lyon, 46, allOe d'Italie, 69364 Lyon, Cedex 7, France Communicated by Prof. R. Tijdeman at the meeting of October 31, 2005 ABSTRACT The linear action of SLfn, Z+) induces lattice partitions on the (n - 1)-dimensional simplex An-b The notion of Farev partition raises naturally from a matricial interpretation of the arithmetical Farey sequence of order r. Such sequence is unique and, consequently, the Fareypartition of order r on Al is unique. In higher dimension no generalized Farey partition is unique. Nevertheless in dimension 3 the number of triangles in the various generalized Farey partitions is always the same which fails to be true in dimension n > 3. Concerning Diophantine approximations, it turns out that the vertices of an n-dimensional Farey partition of order r are the radial projections of the lattice points in Zn~ N [0, r] n whose coordinates are relatively prime. Moreover, we obtain sequences of multidimensional Farey partitions which converge pointwisely. 1. INTRODUCTION The Farey or intermediate fractions are our motivation. We introduce the notion of matricial Farey tree, where matrices of the unimodular group replace the fractions. The matricial approach generalizes to higher dimension the so-called Farey sequence of order r (Hardy and Wright [6, p. 23]). For r 6 N = {1, 2 ... -
Farey Fractions
U.U.D.M. Project Report 2017:24 Farey Fractions Rickard Fernström Examensarbete i matematik, 15 hp Handledare: Andreas Strömbergsson Examinator: Jörgen Östensson Juni 2017 Department of Mathematics Uppsala University Farey Fractions Uppsala University Rickard Fernstr¨om June 22, 2017 1 1 Introduction The Farey sequence of order n is the sequence of all reduced fractions be- tween 0 and 1 with denominator less than or equal to n, arranged in order of increasing size. The properties of this sequence have been thoroughly in- vestigated over the years, out of intrinsic interest. The Farey sequences also play an important role in various more advanced parts of number theory. In the present treatise we give a detailed development of the theory of Farey fractions, following the presentation in Chapter 6.1-2 of the book MNZ = I. Niven, H. S. Zuckerman, H. L. Montgomery, "An Introduction to the Theory of Numbers", fifth edition, John Wiley & Sons, Inc., 1991, but filling in many more details of the proofs. Note that the definition of "Farey sequence" and "Farey fraction" which we give below is apriori different from the one given above; however in Corollary 7 we will see that the two definitions are in fact equivalent. 2 Farey Fractions and Farey Sequences We will assume that a fraction is the quotient of two integers, where the denominator is positive (every rational number can be written in this way). A reduced fraction is a fraction where the greatest common divisor of the 3:5 7 numerator and denominator is 1. E.g. is not a fraction, but is both 4 8 a fraction and a reduced fraction (even though we would normally say that 3:5 7 −1 0 = ). -
A Scaling Property of Farey Fractions
European Journal of Mathematics (2016) 2:383–417 DOI 10.1007/s40879-016-0098-0 RESEARCH ARTICLE A scaling property of Farey fractions Matthias Kunik1 Received: 18 September 2015 / Revised: 26 January 2016 / Accepted: 28 January 2016 / Published online: 25 February 2016 © Springer International Publishing AG 2016 Abstract The Farey sequence of order n consists of all reduced fractions a/b between 0 and 1 with positive denominator b less than or equal to n. The sums of the inverse denominators 1/b of the Farey fractions in prescribed intervals with rational bounds have a simple main term, but the deviations are determined by an interesting sequence of polygonal functions fn.Forn →∞we also obtain a certain limit function, which describes an asymptotic scaling property of functions fn in the vicinity of any fixed fraction a/b and which is independent of a/b. The result can be obtained by using only elementary methods. We also study this limit function and especially its decay behaviour by using the Mellin transform and analytical properties of the Riemann zeta function. Keywords Farey sequences · Riemann zeta function · Mellin transform · Hardy spaces Mathematics Subject Classification 11B57 · 11M06 · 44A20 · 42B30 1 Introduction The Farey sequence Fn of order n consists of all reduced fractions a/b with natural denominator b n in the unit interval [0, 1], arranged in order of increasing size. Dropping just the restriction 0 a/b 1 gives the infinite extended Farey sequence Fext n of order n. We use these notations from Definitions 2.1 and 2.3 and present an overview of new results in each section. -
18.785 Notes
Contents 1 Introduction 4 1.1 What is an automorphic form? . 4 1.2 A rough definition of automorphic forms on Lie groups . 5 1.3 Specializing to G = SL(2; R)....................... 5 1.4 Goals for the course . 7 1.5 Recommended Reading . 7 2 Automorphic forms from elliptic functions 8 2.1 Elliptic Functions . 8 2.2 Constructing elliptic functions . 9 2.3 Examples of Automorphic Forms: Eisenstein Series . 14 2.4 The Fourier expansion of G2k ...................... 17 2.5 The j-function and elliptic curves . 19 3 The geometry of the upper half plane 19 3.1 The topological space ΓnH ........................ 20 3.2 Discrete subgroups of SL(2; R) ..................... 22 3.3 Arithmetic subgroups of SL(2; Q).................... 23 3.4 Linear fractional transformations . 24 3.5 Example: the structure of SL(2; Z)................... 27 3.6 Fundamental domains . 28 3.7 ΓnH∗ as a topological space . 31 3.8 ΓnH∗ as a Riemann surface . 34 3.9 A few basics about compact Riemann surfaces . 35 3.10 The genus of X(Γ) . 37 4 Automorphic Forms for Fuchsian Groups 40 4.1 A general definition of classical automorphic forms . 40 4.2 Dimensions of spaces of modular forms . 42 4.3 The Riemann-Roch theorem . 43 4.4 Proof of dimension formulas . 44 4.5 Modular forms as sections of line bundles . 46 4.6 Poincar´eSeries . 48 4.7 Fourier coefficients of Poincar´eseries . 50 4.8 The Hilbert space of cusp forms . 54 4.9 Basic estimates for Kloosterman sums . 56 4.10 The size of Fourier coefficients for general cusp forms . -
Some Applications of the Spectral Theory of Automorphic Forms
Academic year 2009-2010 Department of Mathematics Some applications of the spectral theory of automorphic forms Research in Mathematics M.Phil Thesis Francois Crucifix Supervisor : Doctor Yiannis Petridis 2 I, Francois Nicolas Bernard Crucifix, confirm that the work presented in this thesis is my own. Where information has been derived from other sources, I confirm that this has been indicated in the thesis. SIGNED CONTENTS 3 Contents Introduction 4 1 Brief overview of general theory 5 1.1 Hyperbolic geometry and M¨obius transformations . ............. 5 1.2 Laplaceoperatorandautomorphicforms. ......... 7 1.3 Thespectraltheorem.............................. .... 8 2 Farey sequence 14 2.1 Fareysetsandgrowthofsize . ..... 14 2.2 Distribution.................................... 16 2.3 CorrelationsofFareyfractions . ........ 18 2.4 Good’sresult .................................... 22 3 Multiplier systems 26 3.1 Definitionsandproperties . ...... 26 3.2 Automorphicformsofnonintegralweights . ......... 27 3.3 Constructionofanewseries. ...... 30 4 Modular knots and linking numbers 37 4.1 Modularknots .................................... 37 4.2 Linkingnumbers .................................. 39 4.3 TheRademacherfunction . 40 4.4 Ghys’result..................................... 41 4.5 SarnakandMozzochi’swork. ..... 43 Conclusion 46 References 47 4 Introduction The aim of this M.Phil thesis is to present my research throughout the past academic year. My topics of interest ranged over a fairly wide variety of subjects. I started with the study of automorphic forms from an analytic point of view by applying spectral methods to the Laplace operator on Riemann hyperbolic surfaces. I finished with a focus on modular knots and their linking numbers and how the latter are related to the theory of well-known analytic functions. My research took many more directions, and I would rather avoid stretching the extensive list of applications, papers and books that attracted my attention. -
Sequences, Their Application and Use in the Field of Mathematics
SEQUENCES, THEIR APPLICATION AND USE IN THE FIELD OF MATHEMATICS Gabe Stevens 5c1 STEVENS GABE – 5CL1 – 2019/2020 Stevens Gabe 5CL1 2019/2020 Table of Contents Table of Contents ............................................................................................................. 1 Introduction ..................................................................................................................... 3 What is a sequence ........................................................................................................... 4 The difference between a set and a sequence ................................................................... 4 Notation ........................................................................................................................... 5 Indexing (Rule) ......................................................................................................................... 6 Recursion ................................................................................................................................. 7 Geometric and arithmetic sequences ................................................................................ 8 Geometric sequences ............................................................................................................... 8 Properties....................................................................................................................................................... 8 Arithmetic sequence ............................................................................................................... -
Arxiv:1710.02996V5 [Math.CO] 21 May 2018 Solutions of Problem II Such That A1 + A2 + ··· + an = 3N − 6, and Triangulations of N-Gons
PARTITIONS OF UNITY IN SL(2; Z), NEGATIVE CONTINUED FRACTIONS, AND DISSECTIONS OF POLYGONS VALENTIN OVSIENKO Abstract. We characterize sequences of positive integers (a1; a2; : : : ; an) for which the 2 × 2 matrix ! ! ! an −1 an−1 −1 a1 −1 ··· is either the identity matrix Id, its negative −Id, or 1 0 1 0 1 0 square root of −Id. This extends a theorem of Conway and Coxeter that classifies such solutions subject to a total positivity restriction. 1. Introduction and main results Let Mn(a1; : : : ; an) 2 SL(2; Z) be the matrix defined by the product ! ! ! an −1 an−1 −1 a1 −1 (1.1) Mn(a1; : : : ; an) := ··· ; 1 0 1 0 1 0 where (a1; a2; : : : ; an) are positive integers. In terms of the generators of SL(2; Z) 0 −1 ! 1 1 ! S = ;T = ; 1 0 0 1 an an−1 a1 the matrix (1.1) reads: Mn(a1; : : : ; an) = T ST S ··· T S. Every matrix A 2 SL(2; Z) can be written in the form (1.1) in many different ways. The goal of this paper is to describe all solutions of the following three equations Mn(a1; : : : ; an) = Id; (Problem I) Mn(a1; : : : ; an) = −Id; (Problem II) 2 Mn(a1; : : : ; an) = −Id: (Problem III) Problem II, with a certain total positivity restriction, was studied in [8, 7] under the name of \frieze patterns". The theorem of Conway and Coxeter [7] establishes a one-to-one correspondence between the arXiv:1710.02996v5 [math.CO] 21 May 2018 solutions of Problem II such that a1 + a2 + ··· + an = 3n − 6, and triangulations of n-gons. -
Arxiv:1403.2928V2 [Math.NT] 21 Mar 2014 B
An arborist's guide to the rationals KATHERINE E. STANGE Abstract. There are two well-known ways to enumerate the positive rational numbers in an infinite binary tree: the Farey/Stern-Brocot tree and the Calkin-Wilf tree. In this brief note, we describe these two trees as `transpose shadows' of a tree of matrices (a result due to Backhouse and Ferreira) via a new proof using yet another famous tree of rationals: the topograph of Conway and Fung. 1. Four Trees In 2000, Calkin and Wilf studied an explicit enumeration of the positive rationals which naturally arranges itself into an infinite tree [5], the first few levels of which are shown here: 1 1 1 2 2 1 1 3 2 3 3 2 3 1 1 4 3 5 2 5 3 4 4 3 5 2 5 3 4 1 1 5 4 7 3 8 5 7 2 7 5 8 3 7 4 5 5 4 7 3 8 5 7 2 7 5 8 3 7 4 5 1 a The generation rule is that a parent b has the following left and right children: a arXiv:1403.2928v2 [math.NT] 21 Mar 2014 b a a+b a+b b Date: October 18, 2018, Draft #1. 2010 Mathematics Subject Classification. Primary: 11B57, Secondary: 11E99. Key words and phrases. special linear group, topograph, M¨obiustransformation, tree, enumeration. The author's research has been supported by NSA Grant Number H98230-14-1-0106 . 1 2 KATHERINE E. STANGE Every positive rational number appears in this tree exactly once. -
Farey Sequences and Ford Circles
Marin Math Circle [email protected] Farey Sequences and Ford Circles Definition 1 Farey Sequence. The Farey sequence of order n, denoted Fn is the sequence of completely reduced fractions between 0 and 1 which, in lowest terms, have denominators less than or equal to n, arranged in order of increasing size. F = 0/1, 1/1 1 { } F = 0/1, 1/2, 1/1 2 { } F = 0/1, 1/3, 1/2, 2/3, 1/1 3 { } Definition 2 Ford Circle. For every rational number p/q in lowest terms, the Ford circle C(p, q) is the circle with center p 1 1 1 ( , ) and radius . This means that C(p, q) is the circle tangent to the x-axis at x = p/q with radius . Observe q 2q2 2q2 2q2 that every small interval of the x-axis contains points of tangency of infinitely many Ford circles. May 11, 2011 1 Lattice Point Geometry Marin Math Circle [email protected] Problems. 1. Suppose that p1/q1 and p2/q2 are two successive terms of Fn. In this problem, we will use Pick’s Theorem to prove that p q p q = 1. Let T be the triangle with vertices (0, 0), (p ,q ), and (p ,q ). 2 1 − 1 2 1 1 2 2 (a) Show that T has no lattice points in its interior, i.e. I(T ) = 0. (b) Show that the only boundary points of T are the vertices of the triangle, i.e. B(T ) = 3. (c) Conclude, using Pick’s Theorem, that 1 A(T )= . -
Automorphic Forms on Shimura Varieties
AUTOMORPHIC FORMS ON SHIMURA VARIETIES ZHIYUAN LI LECTURES SCRIBED BY TONY FENG CONTENTS 1. Overview 3 1.1. Theta lifting 3 1.2. Applications in Number Theory: Kudla’s Program 3 1.3. Applications to algebraic geometry 4 1.4. Kodaira dimension of Shimura varieties 5 2. Modular Forms 6 2.1. Classical modular forms 6 2.2. Vector-valued modular forms 7 2.3. Poincaré series 8 2.4. Properties of modular forms 8 2.5. Dimension of spaces of modular forms 9 2.6. Hecke operators 9 3. Borcherds’ singular theta lift 11 3.1. Overview 11 3.2. Siegel theta functions 11 3.3. Borcherds’ theta lift 13 3.4. Exponentiation 15 3.5. Coefficients 17 3.6. Borcherds infinite products 19 4. Generalized GKZ Theorem 22 4.1. Heegner divisors 22 4.2. Serre duality on modular curves 22 5. The theta correspondence 25 5.1. Heisenberg algebra and Weil representation 25 5.2. Theta correspondence 28 6. Geometry and cohomology on arithmetic manifolds 30 6.1. (g, K )-modules 30 6.2. Relative Lie algebra cohomology 31 6.3. L2-cohomology 31 6.4. Matsushima formula 32 7. Kudla-Millson special theta lifting 34 1 Math 245C 2015 8. Modularity of generating series of special cycles 35 8.1. Construction of special cycles 35 8.2. Theta functions and theta forms 37 2 Math 245C 2015 1. OVERVIEW Let f : G V be a function from a topological group to a vector space, which is “nice.”! We’ll want f to be invariant on the right by some compact subgroup K G , and on the left by some discrete subgroup of G . -
A Farey Sequence of Fibonacci Numbers
A FAREY SEQUENCE OF FIBONACCI NUMBERS KRISHWASWASV1I ALLADI Vlvekananda College, Madras-600004, India The Farey sequence is an old and famous set of fractions associated with the integers. We here show that if we form a Farey sequence of Fibonacci Numbers, the properties of the Farey sequence are remarkably preserved (see [2]). In fact we find that with the new sequence we are able to observe and identify "points of symmetry/' "inter- vals," "generating fractions" and "stages." The paper is divided into three parts. In Part 1, we define "points of symmetry," "intervals" and "generating fractions" and discuss general properties of the Farey sequence of Fibon- acci numbers. In Part 2, we define conjugate fractions and deal with properties associated with intervals. Part 3 con- siders the Farey sequence of Fibonacci numbers as having been divided into stages and contains properties associated with "corresponding fractions" and "corresponding stages." A generalization of the Farey sequence of Fibonacci numbers is given at the end of the third part. th The Farey sequence of Fibonacci numbers of order Fn (where Fn stands for the n term of the Fibonacci se- quence) is the set of all possible fractions Fj/Fj, l=Q, 1, Z 3, —, n - 1, j = 1, 2, 3, —, n (i <j) arranged in ascend- ing order of magnitude. The last term is 1/1, i.e., Fj /F2. The first term is 0/Fn^j. We set FQ = O so that FQ +Ff = F2,F1 = F2=1. For convenience we denote a Farey sequence of Fibonacci numbers by f-f, that of order Fn by f-fn and the th r term in the new Farey sequence of order Fn by f(r)n .