Learning Modern Algebra from Early Attempts to Prove Fermat’S Last Theorem

Total Page:16

File Type:pdf, Size:1020Kb

Learning Modern Algebra from Early Attempts to Prove Fermat’S Last Theorem AMS / MAA TEXTBOOKS VOL 23 Learning Modern Algebra From Early Attempts to Prove Fermat’s Last Theorem Al Cuoco and Joseph J. Rotman i i “book2” — 2013/5/24 — 8:18 — page i — #1 i i 10.1090/text/023 Learning Modern Algebra From Early Attempts to Prove Fermat’s Last Theorem i i i i i i “book2” — 2013/5/24 — 8:18 — page ii — #2 i i c 2013 by The Mathematical Association of America (Incorporated) Library of Congress Control Number: 2013940990 Print ISBN: 978-1-93951-201-7 Electronic ISBN: 978-1-61444-612-5 Printed in the United States of America Current Printing (last digit): 10987654321 i i i i i i “book2” — 2013/5/24 — 8:18 — page iii — #3 i i Learning Modern Algebra From Early Attempts to Prove Fermat’s Last Theorem Al Cuoco EDC, Waltham MA and Joseph J. Rotman University of Illinois at Urbana–Champaign Published and distributed by The Mathematical Association of America i i i i i i “book2” — 2013/5/24 — 8:18 — page iv — #4 i i Committee on Books Frank Farris, Chair MAA Textbooks Editorial Board Zaven A. Karian, Editor Matthias Beck Richard E. Bedient Thomas A. Garrity Charles R. Hampton John Lorch Susan F. Pustejovsky Elsa J. Schaefer Stanley E. Seltzer Kay B. Somers MAA TEXTBOOKS Bridge to Abstract Mathematics, Ralph W. Oberste-Vorth, Aristides Mouzakitis, and Bonita A. Lawrence Calculus Deconstructed:A Second Coursein First-Year Calculus, Zbigniew H. Nitecki Combinatorics: A Guided Tour, David R. Mazur Combinatorics: A Problem Oriented Approach, Daniel A. Marcus Complex Numbers and Geometry, Liang-shin Hahn A Course in Mathematical Modeling, Douglas Mooney and Randall Swift Cryptological Mathematics, Robert Edward Lewand Differential Geometry and its Applications, John Oprea Elementary Cryptanalysis, Abraham Sinkov Elementary Mathematical Models, Dan Kalman An Episodic History of Mathematics: Mathematical Culture Through Problem Solving, Steven G. Krantz Essentials of Mathematics, Margie Hale Field Theory and its Classical Problems, Charles Hadlock Fourier Series, Rajendra Bhatia Game Theory and Strategy, Philip D. Straffin Geometry Revisited, H. S. M. Coxeter and S. L. Greitzer Graph Theory: A Problem Oriented Approach, Daniel Marcus Knot Theory, Charles Livingston Learning Modern Algebra: From Early Attempts to Prove Fermat’s Last Theorem, Al Cuoco and and Joseph J. Rotman Lie Groups: A Problem-Oriented Introduction via Matrix Groups, Harriet Pollatsek Mathematical Connections: A Companion for Teachers and Others, Al Cuoco Mathematical Interest Theory, Second Edition, Leslie Jane Federer Vaaler and James W. Daniel i i i i i i “book2” — 2013/5/24 — 8:18 — page v — #5 i i Mathematical Modeling in the Environment, Charles Hadlock Mathematics for BusinessDecisionsPart 1: Probability and Simulation (electronic text- book), Richard B. Thompson and Christopher G. Lamoureux Mathematics for Business DecisionsPart 2: Calculus and Optimization (electronic text- book), Richard B. Thompson and Christopher G. Lamoureux Mathematics for Secondary School Teachers, Elizabeth G. Bremigan, Ralph J. Bremi- gan, and John D. Lorch The Mathematics of Choice, Ivan Niven The Mathematics of Games and Gambling, Edward Packel Math Through the Ages, William Berlinghoff and Fernando Gouvea Noncommutative Rings, I. N. Herstein Non-Euclidean Geometry, H. S. M. Coxeter Number Theory Through Inquiry, David C. Marshall, Edward Odell, and Michael Star- bird A Primer of Real Functions, Ralph P. Boas A Radical Approach to Lebesgue’s Theory of Integration, David M. Bressoud A Radical Approach to Real Analysis, 2nd edition, David M. Bressoud Real Infinite Series, Daniel D. Bonar and Michael Khoury, Jr. Topology Now!, Robert Messer and Philip Straffin Understanding our Quantitative World, Janet Andersen and Todd Swanson MAA Service Center P.O. Box 91112 Washington, DC 20090-1112 1-800-331-1MAA FAX: 1-301-206-9789 i i i i i i “book2” — 2013/5/24 — 8:18 — page vi — #6 i i i i i i i i “book2” — 2013/5/24 — 8:18 — page vii — #7 i i vii Per Micky: Tutto quello che faccio, lo faccio per te. i i i i i i “book2” — 2013/5/24 — 8:18 — page viii — #8 i i i i i i i i “book2” — 2013/5/24 — 8:18 — page ix — #9 i i Contents Preface xiii SomeFeaturesofThisBook . xiv ANotetoStudents .......................... xv ANotetoInstructors ... ........ ....... ....... xv Notation xvii 1 Early Number Theory 1 1.1 AncientMathematics ........ ....... ....... 1 1.2 Diophantus ........................... 7 GeometryandPythagoreanTriples . 8 TheMethodofDiophantus . 11 Fermat’sLastTheorem . 14 Connections:CongruentNumbers. 16 1.3 Euclid.............................. 20 GreekNumberTheory. 21 DivisionandRemainders . 22 LinearCombinationsandEuclid’sLemma . 24 EuclideanAlgorithm. 30 1.4 NineFundamentalProperties . 36 1.5 Connections........................... 41 Trigonometry ........................ 41 Integration .......................... 42 2 Induction 45 2.1 InductionandApplications . 45 UniqueFactorization. 53 StrongInduction. ........ ....... ....... 57 DifferentialEquations . 60 2.2 BinomialTheorem . ........ ....... ....... 63 Combinatorics ........................ 69 2.3 Connections........................... 73 AnApproachtoInduction . 73 FibonacciSequence . 75 3 Renaissance 81 3.1 ClassicalFormulas . 82 3.2 ComplexNumbers ....................... 91 ix i i i i i i “book2” — 2013/5/29 — 16:18 — page x — #10 i i x Contents AlgebraicOperations . 92 AbsoluteValueandDirection . 99 TheGeometryBehindMultiplication . 101 3.3 RootsandPowers ........ ....... ........ 106 3.4 Connections:DesigningGoodProblems . 116 Norms ............................ 116 PippinsandCheese . 118 Gaussian Integers: Pythagorean Triples Revisited . 119 EisensteinTriplesandDiophantus. 122 NiceBoxes.......................... 123 NiceFunctionsforCalculusProblems . 124 LatticePointTriangles. 126 4 Modular Arithmetic 131 4.1 Congruence ........................... 131 4.2 PublicKeyCodes ........ ....... ........ 149 4.3 CommutativeRings. 154 UnitsandFields ....... ....... ........ 160 SubringsandSubfields. 166 4.4 Connections:JuliusandGregory . 169 4.5 Connections:PatternsinDecimalExpansions . 177 RealNumbers ........................ 177 DecimalExpansionsofRationals . 179 PeriodsandBlocks. 182 5 Abstract Algebra 191 5.1 DomainsandFractionFields . 192 5.2 Polynomials........................... 196 PolynomialFunctions . 204 5.3 Homomorphisms ........ ....... ........ 206 ExtensionsofHomomorphisms . 213 Kernel,Image,andIdeals . 216 5.4 Connections:BooleanThings. 221 Inclusion-Exclusion . 227 6 Arithmetic of Polynomials 233 6.1 Parallels to Z .......................... 233 Divisibility.......................... 233 Roots............................. 239 GreatestCommonDivisors . 243 UniqueFactorization. 248 PrincipalIdealDomains . 255 6.2 Irreducibility .. ........ ....... ........ 259 RootsofUnity ........................ 264 6.3 Connections:LagrangeInterpolation . 270 7 Quotients, Fields, and Classical Problems 277 7.1 QuotientRings ......................... 277 7.2 FieldTheory........................... 287 Characteristics . 287 ExtensionFields . 289 i i i i i i “book2” — 2013/5/24 — 8:18 — page xi — #11 i i Contents xi AlgebraicExtensions . 293 SplittingFields. 300 ClassificationofFiniteFields . 305 7.3 Connections:Ruler–CompassConstructions . 308 Constructing Regular n-gons ................ 320 Gauss’sconstructionofthe17-gon . 322 8 Cyclotomic Integers 329 8.1 ArithmeticinGaussianandEisensteinIntegers . 330 EuclideanDomains . 333 8.2 PrimesUpstairsandPrimesDownstairs . 337 LawsofDecomposition . 339 8.3 Fermat’sLastTheoremforExponent3 . 349 Preliminaries... ........ ....... ....... 350 TheFirstCase ........................ 351 Gauss’sProofoftheSecondCase . 354 8.4 ApproachestotheGeneralCase . 359 Cyclotomicintegers . 360 Kummer,IdealNumbers,andDedekind. 365 8.5 Connections:CountingSumsofSquares . 371 AProofofFermat’sTheoremonDivisors . 373 9 Epilog 379 9.1 AbelandGalois... ........ ....... ....... 379 9.2 SolvabilitybyRadicals . 381 9.3 Symmetry............................ 384 9.4 Groups.............................. 389 9.5 WilesandFermat’sLastTheorem . 396 EllipticIntegralsandEllipticFunctions . 397 CongruentNumbersRevisited. 400 EllipticCurves. 404 A Appendices 409 A.1 Functions ............................ 409 A.2 EquivalenceRelations. 420 A.3 VectorSpaces .... ........ ....... ....... 424 BasesandDimension . 427 LinearTransformations . 435 A.4 Inequalities ........................... 441 A.5 GeneralizedAssociativity. 442 A.6 ACyclotomicIntegerCalculator . 444 EisensteinIntegers . 445 SymmetricPolynomials . 446 AlgebrawithPeriods. 446 References 449 Index 451 About the Authors 459 i i i i i i “book2” — 2013/5/24 — 8:18 — page xii — #12 i i i i i i i i “book2” — 2013/5/24 — 8:18 — page xiii — #13 i i Preface This book is designed for college students who want to teach mathematics in high school, but it can serve as a text for standard abstract algebra courses as well. First courses in abstract algebra usually cover number theory, groups, and commutative rings. We have found that the first encounter with groups is not only inadequate for future teachers of high school mathematics, it is also unsatisfying for other mathematics students. Hence, we focus here on number theory, polynomials, and commutative rings. We introduce groups in our last chapter, for the earlier discussion of commutative rings allows us to explain how groups are used to prove Abel’s Theorem: there is no generalization of the quadratic, cubic, and quartic formulas giving the roots of the general quintic polynomial. A modest proposal: undergraduate abstract algebra
Recommended publications
  • The Parallelogram Law Objective: to Take Students Through the Process
    The Parallelogram Law Objective: To take students through the process of discovery, making a conjecture, further exploration, and finally proof. I. Introduction: Use one of the following… • Geometer’s Sketchpad demonstration • Geogebra demonstration • The introductory handout from this lesson Using one of the introductory activities, allow students to explore and make a conjecture about the relationship between the sum of the squares of the sides of a parallelogram and the sum of the squares of the diagonals. Conjecture: The sum of the squares of the sides of a parallelogram equals the sum of the squares of the diagonals. Ask the question: Can we prove this is always true? II. Activity: Have students look at one more example. Follow the instructions on the exploration handouts, “Demonstrating the Parallelogram Law.” • Give each student a copy of the student handouts, scissors, a glue stick, and two different colored highlighters. Have students follow the instructions. When they get toward the end, they will need to cut very small pieces to fit in the uncovered space. Most likely there will be a very small amount of space left uncovered, or a small amount will extend outside the figure. • After the activity, discuss the results. Did the squares along the two diagonals fit into the squares along all four sides? Since it is unlikely that it will fit exactly, students might question if the relationship is always true. At this point, talk about how we will need to find a convincing proof. III. Go through one or more of the proofs below: Page 1 of 10 MCC@WCCUSD 02/26/13 A.
    [Show full text]
  • CHAPTER 3. VECTOR ALGEBRA Part 1: Addition and Scalar
    CHAPTER 3. VECTOR ALGEBRA Part 1: Addition and Scalar Multiplication for Vectors. §1. Basics. Geometric or physical quantities such as length, area, volume, tempera- ture, pressure, speed, energy, capacity etc. are given by specifying a single numbers. Such quantities are called scalars, because many of them can be measured by tools with scales. Simply put, a scalar is just a number. Quantities such as force, velocity, acceleration, momentum, angular velocity, electric or magnetic field at a point etc are vector quantities, which are represented by an arrow. If the ‘base’ and the ‘head’ of this arrow are B and H repectively, then we denote this vector by −−→BH: Figure 1. Often we use a single block letter in lower case, such as u, v, w, p, q, r etc. to denote a vector. Thus, if we also use v to denote the above vector −−→BH, then v = −−→BH.A vector v has two ingradients: magnitude and direction. The magnitude is the length of the arrow representing v, and is denoted by v . In case v = −−→BH, certainly we | | have v = −−→BH for the magnitude of v. The meaning of the direction of a vector is | | | | self–evident. Two vectors are considered to be equal if they have the same magnitude and direction. You recognize two equal vectors in drawing, if their representing arrows are parallel to each other, pointing in the same way, and have the same length 1 Figure 2. For example, if A, B, C, D are vertices of a parallelogram, followed in that order, then −→AB = −−→DC and −−→AD = −−→BC: Figure 3.
    [Show full text]
  • LINEAR ALGEBRA METHODS in COMBINATORICS László Babai
    LINEAR ALGEBRA METHODS IN COMBINATORICS L´aszl´oBabai and P´eterFrankl Version 2.1∗ March 2020 ||||| ∗ Slight update of Version 2, 1992. ||||||||||||||||||||||| 1 c L´aszl´oBabai and P´eterFrankl. 1988, 1992, 2020. Preface Due perhaps to a recognition of the wide applicability of their elementary concepts and techniques, both combinatorics and linear algebra have gained increased representation in college mathematics curricula in recent decades. The combinatorial nature of the determinant expansion (and the related difficulty in teaching it) may hint at the plausibility of some link between the two areas. A more profound connection, the use of determinants in combinatorial enumeration goes back at least to the work of Kirchhoff in the middle of the 19th century on counting spanning trees in an electrical network. It is much less known, however, that quite apart from the theory of determinants, the elements of the theory of linear spaces has found striking applications to the theory of families of finite sets. With a mere knowledge of the concept of linear independence, unexpected connections can be made between algebra and combinatorics, thus greatly enhancing the impact of each subject on the student's perception of beauty and sense of coherence in mathematics. If these adjectives seem inflated, the reader is kindly invited to open the first chapter of the book, read the first page to the point where the first result is stated (\No more than 32 clubs can be formed in Oddtown"), and try to prove it before reading on. (The effect would, of course, be magnified if the title of this volume did not give away where to look for clues.) What we have said so far may suggest that the best place to present this material is a mathematics enhancement program for motivated high school students.
    [Show full text]
  • Problems in Abstract Algebra
    STUDENT MATHEMATICAL LIBRARY Volume 82 Problems in Abstract Algebra A. R. Wadsworth 10.1090/stml/082 STUDENT MATHEMATICAL LIBRARY Volume 82 Problems in Abstract Algebra A. R. Wadsworth American Mathematical Society Providence, Rhode Island Editorial Board Satyan L. Devadoss John Stillwell (Chair) Erica Flapan Serge Tabachnikov 2010 Mathematics Subject Classification. Primary 00A07, 12-01, 13-01, 15-01, 20-01. For additional information and updates on this book, visit www.ams.org/bookpages/stml-82 Library of Congress Cataloging-in-Publication Data Names: Wadsworth, Adrian R., 1947– Title: Problems in abstract algebra / A. R. Wadsworth. Description: Providence, Rhode Island: American Mathematical Society, [2017] | Series: Student mathematical library; volume 82 | Includes bibliographical references and index. Identifiers: LCCN 2016057500 | ISBN 9781470435837 (alk. paper) Subjects: LCSH: Algebra, Abstract – Textbooks. | AMS: General – General and miscellaneous specific topics – Problem books. msc | Field theory and polyno- mials – Instructional exposition (textbooks, tutorial papers, etc.). msc | Com- mutative algebra – Instructional exposition (textbooks, tutorial papers, etc.). msc | Linear and multilinear algebra; matrix theory – Instructional exposition (textbooks, tutorial papers, etc.). msc | Group theory and generalizations – Instructional exposition (textbooks, tutorial papers, etc.). msc Classification: LCC QA162 .W33 2017 | DDC 512/.02–dc23 LC record available at https://lccn.loc.gov/2016057500 Copying and reprinting. Individual readers of this publication, and nonprofit libraries acting for them, are permitted to make fair use of the material, such as to copy select pages for use in teaching or research. Permission is granted to quote brief passages from this publication in reviews, provided the customary acknowledgment of the source is given. Republication, systematic copying, or multiple reproduction of any material in this publication is permitted only under license from the American Mathematical Society.
    [Show full text]
  • Abstract Algebra
    Abstract Algebra Martin Isaacs, University of Wisconsin-Madison (Chair) Patrick Bahls, University of North Carolina, Asheville Thomas Judson, Stephen F. Austin State University Harriet Pollatsek, Mount Holyoke College Diana White, University of Colorado Denver 1 Introduction What follows is a report summarizing the proposals of a group charged with developing recommendations for undergraduate curricula in abstract algebra.1 We begin by articulating the principles that shaped the discussions that led to these recommendations. We then indicate several learning goals; some of these address specific content areas and others address students' general development. Next, we include three sample syllabi, each tailored to meet the needs of specific types of institutions and students. Finally, we present a brief list of references including sample texts. 2 Guiding Principles We lay out here several principles that underlie our recommendations for undergraduate Abstract Algebra courses. Although these principles are very general, we indicate some of their specific implications in the discussions of learning goals and curricula below. Diversity of students We believe that a course in Abstract Algebra is valuable for a wide variety of students, including mathematics majors, mathematics education majors, mathematics minors, and majors in STEM disciplines such as physics, chemistry, and computer science. Such a course is essential preparation for secondary teaching and for many doctoral programs in mathematics. Moreover, algebra can capture the imagination of students whose attraction to mathematics is primarily to structure and abstraction (for example, 1As with any document that is produced by a committee, there were some disagreements and compromises. The committee members had many lively and spirited communications on what undergraduate Abstract Algebra should look like for the next ten years.
    [Show full text]
  • Abstract Algebra
    Abstract Algebra Paul Melvin Bryn Mawr College Fall 2011 lecture notes loosely based on Dummit and Foote's text Abstract Algebra (3rd ed) Prerequisite: Linear Algebra (203) 1 Introduction Pure Mathematics Algebra Analysis Foundations (set theory/logic) G eometry & Topology What is Algebra? • Number systems N = f1; 2; 3;::: g \natural numbers" Z = f:::; −1; 0; 1; 2;::: g \integers" Q = ffractionsg \rational numbers" R = fdecimalsg = pts on the line \real numbers" p C = fa + bi j a; b 2 R; i = −1g = pts in the plane \complex nos" k polar form re iθ, where a = r cos θ; b = r sin θ a + bi b r θ a p Note N ⊂ Z ⊂ Q ⊂ R ⊂ C (all proper inclusions, e.g. 2 62 Q; exercise) There are many other important number systems inside C. 2 • Structure \binary operations" + and · associative, commutative, and distributive properties \identity elements" 0 and 1 for + and · resp. 2 solve equations, e.g. 1 ax + bx + c = 0 has two (complex) solutions i p −b ± b2 − 4ac x = 2a 2 2 2 2 x + y = z has infinitely many solutions, even in N (thei \Pythagorian triples": (3,4,5), (5,12,13), . ). n n n 3 x + y = z has no solutions x; y; z 2 N for any fixed n ≥ 3 (Fermat'si Last Theorem, proved in 1995 by Andrew Wiles; we'll give a proof for n = 3 at end of semester). • Abstract systems groups, rings, fields, vector spaces, modules, . A group is a set G with an associative binary operation ∗ which has an identity element e (x ∗ e = x = e ∗ x for all x 2 G) and inverses for each of its elements (8 x 2 G; 9 y 2 G such that x ∗ y = y ∗ x = e).
    [Show full text]
  • 1 Algebra Vs. Abstract Algebra 2 Abstract Number Systems in Linear
    MATH 2135, LINEAR ALGEBRA, Winter 2017 and multiplication is also called the “logical and” operation. For example, we Handout 1: Lecture Notes on Fields can calculate like this: Peter Selinger 1 · ((1 + 0) + 1) + 1 = 1 · (1 + 1) + 1 = 1 · 0 + 1 = 0+1 1 Algebra vs. abstract algebra = 1. Operations such as addition and multiplication can be considered at several dif- 2 Abstract number systems in linear algebra ferent levels: • Arithmetic deals with specific calculation rules, such as 8 + 3 = 11. It is As you already know, Linear Algebra deals with subjects such as matrix multi- usually taught in elementary school. plication, linear combinations, solutions of systems of linear equations, and so on. It makes heavy use of addition, subtraction, multiplication, and division of • Algebra deals with the idea that operations satisfy laws, such as a(b+c)= scalars (think, for example, of the rule for multiplying matrices). ab + ac. Such laws can be used, among other things, to solve equations It turns out that most of what we do in linear algebra does not rely on the spe- such as 3x + 5 = 14. cific laws of arithmetic. Linear algebra works equally well over “alternative” • Abstract algebra is the idea that we can use the laws of algebra, such as arithmetics. a(b + c) = ab + ac, while abandoning the rules of arithmetic, such as Example 2.1. Consider multiplying two matrices, using arithmetic modulo 2 8 + 3 = 11. Thus, in abstract algebra, we are able to speak of entirely instead of the usual arithmetic. different “number” systems, for example, systems in which 1+1=0.
    [Show full text]
  • Algebraic Topology - Wikipedia, the Free Encyclopedia Page 1 of 5
    Algebraic topology - Wikipedia, the free encyclopedia Page 1 of 5 Algebraic topology From Wikipedia, the free encyclopedia Algebraic topology is a branch of mathematics which uses tools from abstract algebra to study topological spaces. The basic goal is to find algebraic invariants that classify topological spaces up to homeomorphism, though usually most classify up to homotopy equivalence. Although algebraic topology primarily uses algebra to study topological problems, using topology to solve algebraic problems is sometimes also possible. Algebraic topology, for example, allows for a convenient proof that any subgroup of a free group is again a free group. Contents 1 The method of algebraic invariants 2 Setting in category theory 3 Results on homology 4 Applications of algebraic topology 5 Notable algebraic topologists 6 Important theorems in algebraic topology 7 See also 8 Notes 9 References 10 Further reading The method of algebraic invariants An older name for the subject was combinatorial topology , implying an emphasis on how a space X was constructed from simpler ones (the modern standard tool for such construction is the CW-complex ). The basic method now applied in algebraic topology is to investigate spaces via algebraic invariants by mapping them, for example, to groups which have a great deal of manageable structure in a way that respects the relation of homeomorphism (or more general homotopy) of spaces. This allows one to recast statements about topological spaces into statements about groups, which are often easier to prove. Two major ways in which this can be done are through fundamental groups, or more generally homotopy theory, and through homology and cohomology groups.
    [Show full text]
  • Ill.'Dept. of Mathemat Available in Hard Copy Due To:Copyright,Restrictions
    Docusty4 REWIRE . ED184843 E 030 460 AUTHOR Kogan, B. Yu TITLE The Application àf Me anics to Ge setry. Popullr Lectures in Mathematice. 'INSTITUTION Cbicag Univ. Ill.'Dept. of Mathemat s. SPONS AGENCY National Science Foundation, Nashington;.D.C. PUB DATE 74 GRANT NSLY-3-13847(MA) NOTE 65p.; ?or related documents, see SE 030 4-61-465. Not available in hard copy due to:copyright,restrictions. Translated and adapted from the Russian edition. 'AVAILABLE FROM The University of Chicago Press, Chicaip, IL 60637. (Order No. 450163; $4.50). EDRS PRICE MP01 Plus Postage.. PC Not Available from ED4S. DESZRIPTORS *College Mathematics; Force; Geometric Concepti; *Geometry; Higher Education; Lecture Method; *Mathematical Applications; *Mathemaiics; *Mechanics (Physics) ABBTRAiT Presented in thir traInslktion are three chapters. Chapter I discusses the compbsitivn of forces and several theoreas of geometry are proved using the'fundamental conceptsand certain laws of statics. Chapter II discusses the perpetual motion postRlate; several geometri:l.theorems are proved, uting the postulate t4t p9rp ual motion is iipossib?e. In Chapter ILI,' the Center of Gray Potential Energy, and Vork are discussed. (MK) a N'4 , * Reproductions supplied by EDRS are the best that can be madel * * from the original document. * U.S. DIEPARTMINT OP WEALTH. g.tpUCATION WILPARI - aATIONAL INSTITTLISM Oa IDUCATION THIS DOCUMENT HAS BEEN REPRO. atiCED EXACTLMAIS RECEIVED Flicw THE PERSON OR ORGANIZATION DRPOIN- ATINO IT POINTS'OF VIEW OR OPINIONS STATED DO NOT NECESSARILY WEPRE.' se NT OFFICIAL NATIONAL INSTITUTE OF EDUCATION POSITION OR POLICY 0 * "PERMISSION TO REPRODUC THIS MATERIAL IN MICROFICHE dIlLY HAS SEEN GRANTED BY TO THE EDUCATIONAL RESOURCES INFORMATION CENTER (ERIC)." -Mlk -1 Popular Lectures In nithematics.
    [Show full text]
  • Introduction to Abstract Algebra (Math 113)
    Introduction to Abstract Algebra (Math 113) Alexander Paulin, with edits by David Corwin FOR FALL 2019 MATH 113 002 ONLY Contents 1 Introduction 4 1.1 What is Algebra? . 4 1.2 Sets . 6 1.3 Functions . 9 1.4 Equivalence Relations . 12 2 The Structure of + and × on Z 15 2.1 Basic Observations . 15 2.2 Factorization and the Fundamental Theorem of Arithmetic . 17 2.3 Congruences . 20 3 Groups 23 1 3.1 Basic Definitions . 23 3.1.1 Cayley Tables for Binary Operations and Groups . 28 3.2 Subgroups, Cosets and Lagrange's Theorem . 30 3.3 Generating Sets for Groups . 35 3.4 Permutation Groups and Finite Symmetric Groups . 40 3.4.1 Active vs. Passive Notation for Permutations . 40 3.4.2 The Symmetric Group Sym3 . 43 3.4.3 Symmetric Groups in General . 44 3.5 Group Actions . 52 3.5.1 The Orbit-Stabiliser Theorem . 55 3.5.2 Centralizers and Conjugacy Classes . 59 3.5.3 Sylow's Theorem . 66 3.6 Symmetry of Sets with Extra Structure . 68 3.7 Normal Subgroups and Isomorphism Theorems . 73 3.8 Direct Products and Direct Sums . 83 3.9 Finitely Generated Abelian Groups . 85 3.10 Finite Abelian Groups . 90 3.11 The Classification of Finite Groups (Proofs Omitted) . 95 4 Rings, Ideals, and Homomorphisms 100 2 4.1 Basic Definitions . 100 4.2 Ideals, Quotient Rings and the First Isomorphism Theorem for Rings . 105 4.3 Properties of Elements of Rings . 109 4.4 Polynomial Rings . 112 4.5 Ring Extensions . 115 4.6 Field of Fractions .
    [Show full text]
  • An Elementary System of Axioms for Euclidean Geometry Based on Symmetry Principles
    An Elementary System of Axioms for Euclidean Geometry based on Symmetry Principles Boris Čulina Department of Mathematics, University of Applied Sciences Velika Gorica, Zagrebačka cesta 5, Velika Gorica, CROATIA email: [email protected] arXiv:2105.14072v1 [math.HO] 28 May 2021 1 Abstract. In this article I develop an elementary system of axioms for Euclidean geometry. On one hand, the system is based on the symmetry principles which express our a priori ignorant approach to space: all places are the same to us (the homogeneity of space), all directions are the same to us (the isotropy of space) and all units of length we use to create geometric figures are the same to us (the scale invariance of space). On the other hand, through the process of algebraic simplification, this system of axioms directly provides the Weyl’s system of axioms for Euclidean geometry. The system of axioms, together with its a priori interpretation, offers new views to philosophy and pedagogy of mathematics: (i) it supports the thesis that Euclidean geometry is a priori, (ii) it supports the thesis that in modern mathematics the Weyl’s system of axioms is dominant to the Euclid’s system because it reflects the a priori underlying symmetries, (iii) it gives a new and promising approach to learn geometry which, through the Weyl’s system of axioms, leads from the essential geometric symmetry principles of the mathematical nature directly to modern mathematics. keywords: symmetry, Euclidean geometry, axioms, Weyl’s axioms, phi- losophy of geometry, pedagogy of geometry 1 Introduction The connection of Euclidean geometry with symmetries has a long history.
    [Show full text]
  • Fundamental Theorems in Mathematics
    SOME FUNDAMENTAL THEOREMS IN MATHEMATICS OLIVER KNILL Abstract. An expository hitchhikers guide to some theorems in mathematics. Criteria for the current list of 243 theorems are whether the result can be formulated elegantly, whether it is beautiful or useful and whether it could serve as a guide [6] without leading to panic. The order is not a ranking but ordered along a time-line when things were writ- ten down. Since [556] stated “a mathematical theorem only becomes beautiful if presented as a crown jewel within a context" we try sometimes to give some context. Of course, any such list of theorems is a matter of personal preferences, taste and limitations. The num- ber of theorems is arbitrary, the initial obvious goal was 42 but that number got eventually surpassed as it is hard to stop, once started. As a compensation, there are 42 “tweetable" theorems with included proofs. More comments on the choice of the theorems is included in an epilogue. For literature on general mathematics, see [193, 189, 29, 235, 254, 619, 412, 138], for history [217, 625, 376, 73, 46, 208, 379, 365, 690, 113, 618, 79, 259, 341], for popular, beautiful or elegant things [12, 529, 201, 182, 17, 672, 673, 44, 204, 190, 245, 446, 616, 303, 201, 2, 127, 146, 128, 502, 261, 172]. For comprehensive overviews in large parts of math- ematics, [74, 165, 166, 51, 593] or predictions on developments [47]. For reflections about mathematics in general [145, 455, 45, 306, 439, 99, 561]. Encyclopedic source examples are [188, 705, 670, 102, 192, 152, 221, 191, 111, 635].
    [Show full text]