DOCSLIB.ORG

Problems in Abstract Algebra

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read 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. Permissions to reuse portions of AMS publication content are handled by Copyright Clearance Center’s RightsLink service. For more information, please visit: http:// www.ams.org/rightslink. Send requests for translation rights and licensed reprints to reprint-permission @ams.org. Excluded from these provisions is material for which the author holds copyright. In such cases, requests for permission to reuse or reprint material should be addressed directly to the author(s). Copyright ownership is indicated on the copyright page, or on the lower right-hand corner of the first page of each article within proceedings volumes. c 2017 by the American Mathematical Society. All rights reserved. The American Mathematical Society retains all rights except those granted to the United States Government. Printed in the United States of America. ∞ The paper used in this book is acid-free and falls within the guidelines established to ensure permanence and durability. Visit the AMS home page at http://www.ams.org/ 10987654321 222120191817 Contents Preface........................... vii Introduction........................ 1 §0.1. Notation..................... 3 §0.2. Zorn’sLemma.................. 5 Chapter 1. Integers and Integers mod n .......... 7 Chapter2.Groups..................... 13 §2.1. Groups, subgroups, and cosets . 13 §2.2. Group homomorphisms and factor groups . 25 §2.3. Groupactions.................. 32 §2.4. Symmetric and alternating groups . 36 §2.5. p-groups..................... 41 §2.6. Sylowsubgroups................. 43 §2.7. Semidirect products of groups . 44 §2.8. Free groups and groups by generators and relations 53 §2.9. Nilpotent, solvable, and simple groups . 58 §2.10.Finiteabeliangroups .............. 66 Chapter3.Rings...................... 73 §3.1. Rings,subrings,andideals............ 73 iii iv Contents §3.2. Factor rings and ring homomorphisms . 89 §3.3. Polynomial rings and evaluation maps . 97 §3.4. Integral domains, quotient fields . 100 §3.5. Maximal ideals and prime ideals . 103 §3.6. Divisibility and principal ideal domains . 107 §3.7. Unique factorization domains . 115 Chapter 4. Linear Algebra and Canonical Forms of Linear Transformations ................ 125 §4.1. Vector spaces and linear dependence . 125 §4.2. Linear transformations and matrices . 132 §4.3. Dualspace.................... 139 §4.4. Determinants .................. 142 §4.5. Eigenvalues and eigenvectors, triangulation and diagonalization . 150 §4.6. Minimal polynomials of a linear transformation andprimarydecomposition ........... 155 §4.7. T -cyclic subspaces and T -annihilators ...... 161 §4.8. Projectionmaps................. 164 §4.9. Cyclic decomposition and rational and Jordan canonicalforms................. 167 §4.10. The exponential of a matrix . 177 §4.11. Symmetric and orthogonal matrices over R .... 180 §4.12. Group theory problems using linear algebra . 187 Chapter 5. Fields and Galois Theory . 191 §5.1. Algebraic elements and algebraic field extensions . 192 §5.2. Constructibility by compass and straightedge . 199 §5.3. Transcendental extensions . 202 §5.4. Criteria for irreducibility of polynomials . 205 §5.5. Splitting fields, normal field extensions, and Galois groups...................... 208 §5.6. Separability and repeated roots . 216 Contents v §5.7. Finitefields................... 223 §5.8. Galois field extensions . 226 §5.9. Cyclotomic polynomials and cyclotomic extensions 234 §5.10. Radical extensions, norms, and traces . 244 §5.11. Solvability by radicals . 253 SuggestionsforFurtherReading .............. 257 Bibliography........................ 259 IndexofNotation ..................... 261 Subject and Terminology Index . 267 Preface It is a truism that, for most students, solving problems is a vital part of learning a mathematical subject well. Furthermore, I think students learn the most from challenging problems that demand se- rious thought and help develop a deeper understanding of important ideas. When teaching abstract algebra, I found it frustrating that most textbooks did not have enough interesting or really demanding problems. This led me to provide regular supplementary problem handouts. The handouts usually included a few particularly chal- lenging “optional problems,” which the students were free to work on or not, but they would receive some extra credit for turning in correct solutions. My problem handouts were the primary source for the problems in this book. They were used in teaching Math 100, University of California, San Diego’s yearlong honors level course se- quence in abstract algebra, and for the first term of Math 200, the graduate abstract algebra sequence. I hope this problem book will be a useful resource for students learning abstract algebra and for professors wanting to go beyond their textbook’s problems. To make this book somewhat more self-contained and indepen- dent of any particular text, I have included definitions of most con- cepts and statements of key theorems (including a few short proofs). This will mitigate the problem that texts do not completely agree on some definitions; likewise, there are different names and versions of vii viii Preface some theorems. For example, what is here called the Fundamental Homomorphism Theorem many authors call the First Isomorphism Theorem; so what is here the First Isomorphism Theorem they call the Second Isomorphism Theorem, etc. References for omitted proofs are provided except when they can be found in any text. Some of the problems given here appear as theorems or problems in many texts. They are included if they give results worth knowing or if they are building blocks for other problems. Many of the problems have multiple parts; this makes it possible to develop a topic more thoroughly than what can be done in just a few sentences. Multipart problems can also provide paths to more difficult results. I would like to thank Richard Elman for helpful suggestions and references. I would also like to thank Skip Garibaldi for much valuable feedback and for suggesting some problems. Bibliography When available, Mathematical Reviews reference numbers are in- dicated at the end of each bibliographic entry as MR∗∗∗∗∗∗∗.See www.ams.org/mathscinet. 1. Artin, Michael, Algebra, second ed., Prentice Hall, Boston, MA, 2011. 2. Atiyah, Michael F. and Macdonald, Ian G., Introduction to commuta- tive algebra, Addison-Wesley Publishing Co., Reading, Mass.-London- Don Mills, Ont., 1969. MR0242802 3. Borevich, Zenon I. and Shafarevich, Igor R., Number theory, Pure and Applied Mathematics, Vol. 20, Academic Press, New York-London, 1966. MR0195803 4. Cox, David A., Galois theory, second ed., Pure and Applied Math- ematics (Hoboken), John Wiley & Sons, Inc., Hoboken, NJ, 2012. MR2919975 5. Dummit, David S. and Foote, Richard M., Abstract algebra,thirded., John Wiley & Sons, Inc., Hoboken, NJ, 2004. MR2286236 6. Ebbinghaus, Heinz-Dieter; Hermes, Hans; Hirzebruch, Friedrich; Koecher, Max; Mainzer, Klaus; Neukirch, J¨urgen; Prestel, Alexander; and Remmert, Reinhold, Numbers, Graduate Texts in Mathematics, vol. 123, Springer-Verlag, New York, 1990, Readings in Mathematics. MR1066206 7. Hall, Jr., Marshall, The theory of groups, Chelsea Publishing Co., New York, 1976, Reprint of the 1968 edition. MR0414669 8. Hoffman, Kenneth and Kunze, Ray, Linear algebra, Second edition, Prentice-Hall, Inc., Englewood Cliffs, N.J., 1971. MR0276251 259 260 Bibliography 9. Hungerford, Thomas W., Algebra, Graduate Texts in Mathematics, vol. 73, Springer-Verlag, New York-Berlin, 1980, Reprint
Load more

Recommended publications
  • On Regular Matrix Semirings
    Thai Journal of Mathematics Volume 7 (2009) Number 1 : 69{75 www.math.science.cmu.ac.th/thaijournal Online ISSN 1686-0209 On Regular Matrix Semirings S. Chaopraknoi, K. Savettaseranee and P. Lertwichitsilp Abstract : A ring R is called a (von Neumann) regular ring if for every x 2 R; x = xyx for some y 2 R. It is well-known that for any ring R and any positive integer n, the full matrix ring Mn(R) is regular if and only if R is a regular ring. This paper examines this property on any additively commutative semiring S with zero. The regularity of S is defined analogously. We show that for a positive integer n, if Mn(S) is a regular semiring, then S is a regular semiring but the converse need not be true for n = 2. And for n ≥ 3, Mn(S) is a regular semiring if and only if S is a regular ring. Keywords : Matrix ring; Matrix semiring; Regular ring; Regular semiring. 2000 Mathematics Subject Classification : 16Y60, 16S50. 1 Introduction A triple (S; +; ·) is called a semiring if (S; +) and (S; ·) are semigroups and · is distributive over +. An element 0 2 S is called a zero of the semiring (S; +; ·) if x + 0 = 0 + x = x and x · 0 = 0 · x = 0 for all x 2 S. Note that every semiring contains at most one zero. A semiring (S; +; ·) is called additively [multiplicatively] commutative if x + y = y + x [x · y = y · x] for all x; y 2 S: We say that (S; +; ·) is commutative if it is both additively and multiplicatively commutative.
    [Show full text]
  • 1 Jun 2020 Flat Semimodules & Von Neumann Regular Semirings
    Flat Semimodules & von Neumann Regular Semirings* Jawad Abuhlail† Rangga Ganzar Noegraha‡ [email protected] [email protected] Department of Mathematics and Statistics Universitas Pertamina King Fahd University of Petroleum & Minerals Jl. Teuku Nyak Arief 31261Dhahran,KSA Jakarta12220,Indonesia June 2, 2020 Abstract Flat modules play an important role in the study of the category of modules over rings and in the characterization of some classes of rings. We study the e-flatness for semimodules introduced by the first author using his new notion of exact sequences of semimodules and its relationships with other notions of flatness for semimodules over semirings. We also prove that a subtractive semiring over which every right (left) semimodule is e-flat is a von Neumann regular semiring. Introduction Semirings are, roughly, rings not necessarily with subtraction. They generalize both rings and distributive bounded lattices and have, along with their semimodules many applications in Com- arXiv:1907.07047v2 [math.RA] 1 Jun 2020 puter Science and Mathematics (e.g., [1, 2, 3]). Some applications can be found in Golan’s book [4], which is our main reference on this topic. A systematic study of semimodules over semirings was carried out by M. Takahashi in a series of papers 1981-1990. However, he defined two main notions in a way that turned out to be not natural. Takahashi’s tensor products [5] did not satisfy the expected Universal Property. On *MSC2010: Primary 16Y60; Secondary 16D40, 16E50, 16S50 Key Words: Semirings; Semimodules; Flat Semimodules; Exact Sequences; Von Neumann Regular Semirings; Matrix Semirings The authors would like to acknowledge the support provided by the Deanship of Scientific Research (DSR) at King Fahd University of Petroleum & Minerals (KFUPM) for funding this work through projects No.
    [Show full text]
  • Subset Semirings
    University of New Mexico UNM Digital Repository Faculty and Staff Publications Mathematics 2013 Subset Semirings Florentin Smarandache University of New Mexico, [email protected] W.B. Vasantha Kandasamy [email protected] Follow this and additional works at: https://digitalrepository.unm.edu/math_fsp Part of the Algebraic Geometry Commons, Analysis Commons, and the Other Mathematics Commons Recommended Citation W.B. Vasantha Kandasamy & F. Smarandache. Subset Semirings. Ohio: Educational Publishing, 2013. This Book is brought to you for free and open access by the Mathematics at UNM Digital Repository. It has been accepted for inclusion in Faculty and Staff Publications by an authorized administrator of UNM Digital Repository. For more information, please contact [email protected], [email protected], [email protected]. Subset Semirings W. B. Vasantha Kandasamy Florentin Smarandache Educational Publisher Inc. Ohio 2013 This book can be ordered from: Education Publisher Inc. 1313 Chesapeake Ave. Columbus, Ohio 43212, USA Toll Free: 1-866-880-5373 Copyright 2013 by Educational Publisher Inc. and the Authors Peer reviewers: Marius Coman, researcher, Bucharest, Romania. Dr. Arsham Borumand Saeid, University of Kerman, Iran. Said Broumi, University of Hassan II Mohammedia, Casablanca, Morocco. Dr. Stefan Vladutescu, University of Craiova, Romania. Many books can be downloaded from the following Digital Library of Science: http://www.gallup.unm.edu/eBooks-otherformats.htm ISBN-13: 978-1-59973-234-3 EAN: 9781599732343 Printed in the United States of America 2 CONTENTS Preface 5 Chapter One INTRODUCTION 7 Chapter Two SUBSET SEMIRINGS OF TYPE I 9 Chapter Three SUBSET SEMIRINGS OF TYPE II 107 Chapter Four NEW SUBSET SPECIAL TYPE OF TOPOLOGICAL SPACES 189 3 FURTHER READING 255 INDEX 258 ABOUT THE AUTHORS 260 4 PREFACE In this book authors study the new notion of the algebraic structure of the subset semirings using the subsets of rings or semirings.
    [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]
  • The Heisenberg Group Fourier Transform
    THE HEISENBERG GROUP FOURIER TRANSFORM NEIL LYALL Contents 1. Fourier transform on Rn 1 2. Fourier analysis on the Heisenberg group 2 2.1. Representations of the Heisenberg group 2 2.2. Group Fourier transform 3 2.3. Convolution and twisted convolution 5 3. Hermite and Laguerre functions 6 3.1. Hermite polynomials 6 3.2. Laguerre polynomials 9 3.3. Special Hermite functions 9 4. Group Fourier transform of radial functions on the Heisenberg group 12 References 13 1. Fourier transform on Rn We start by presenting some standard properties of the Euclidean Fourier transform; see for example [6] and [4]. Given f ∈ L1(Rn), we define its Fourier transform by setting Z fb(ξ) = e−ix·ξf(x)dx. Rn n ih·ξ If for h ∈ R we let (τhf)(x) = f(x + h), then it follows that τdhf(ξ) = e fb(ξ). Now for suitable f the inversion formula Z f(x) = (2π)−n eix·ξfb(ξ)dξ, Rn holds and we see that the Fourier transform decomposes a function into a continuous sum of characters (eigenfunctions for translations). If A is an orthogonal matrix and ξ is a column vector then f[◦ A(ξ) = fb(Aξ) and from this it follows that the Fourier transform of a radial function is again radial. In particular the Fourier transform −|x|2/2 n of Gaussians take a particularly nice form; if G(x) = e , then Gb(ξ) = (2π) 2 G(ξ). In general the Fourier transform of a radial function can always be explicitly expressed in terms of a Bessel 1 2 NEIL LYALL transform; if g(x) = g0(|x|) for some function g0, then Z ∞ n 2−n n−1 gb(ξ) = (2π) 2 g0(r)(r|ξ|) 2 J n−2 (r|ξ|)r dr, 0 2 where J n−2 is a Bessel function.
    [Show full text]
  • Derivations of a Matrix Ring Containing a Subring of Triangular Matrices S
    ISSN 1066-369X, Russian Mathematics (Iz. VUZ), 2011, Vol. 55, No. 11, pp. 18–26. c Allerton Press, Inc., 2011. Original Russian Text c S.G. Kolesnikov and N.V. Mal’tsev, 2011, published in Izvestiya Vysshikh Uchebnykh Zavedenii. Matematika, 2011, No. 11, pp. 23–33. Derivations of a Matrix Ring Containing a Subring of Triangular Matrices S. G. Kolesnikov1* andN.V.Mal’tsev2** 1Institute of Mathematics, Siberian Federal University, pr. Svobodnyi 79, Krasnoyarsk, 660041 Russia 2Institute of Core Undergraduate Programs, Siberian Federal University, 26 ul. Akad. Kirenskogo 26, Krasnoyarsk, 660041 Russia Received October 22, 2010 Abstract—We describe the derivations (including Jordan and Lie ones) of finitary matrix rings, containing a subring of triangular matrices, over an arbitrary associative ring with identity element. DOI: 10.3103/S1066369X1111003X Keywords and phrases: finitary matrix, derivations of rings, Jordan and Lie derivations of rings. INTRODUCTION An endomorphism ϕ of an additive group of a ring K is called a derivation if ϕ(ab)=ϕ(a)b + aϕ(b) for any a, b ∈ K. Derivations of the Lie and Jordan rings associated with K are called, respectively, the Lie and Jordan derivations of the ring K; they are denoted, respectively, by Λ(K) and J(K). (We obtain them by replacing the multiplication in K with the Lie multiplication a ∗ b = ab − ba and the Jordan one a ◦ b = ab + ba, respectively.) In 1957 I. N. Herstein proved [1] that every Jordan derivation of a primary ring of characteristic =2 is a derivation. His theorem was generalized by several authors ([2–9] et al.) for other classes of rings and algebras.
    [Show full text]
  • Schaum's Outline of Linear Algebra (4Th Edition)
    SCHAUM’S SCHAUM’S outlines outlines Linear Algebra Fourth Edition Seymour Lipschutz, Ph.D. Temple University Marc Lars Lipson, Ph.D. University of Virginia Schaum’s Outline Series New York Chicago San Francisco Lisbon London Madrid Mexico City Milan New Delhi San Juan Seoul Singapore Sydney Toronto Copyright © 2009, 2001, 1991, 1968 by The McGraw-Hill Companies, Inc. All rights reserved. Except as permitted under the United States Copyright Act of 1976, no part of this publication may be reproduced or distributed in any form or by any means, or stored in a database or retrieval system, without the prior writ- ten permission of the publisher. ISBN: 978-0-07-154353-8 MHID: 0-07-154353-8 The material in this eBook also appears in the print version of this title: ISBN: 978-0-07-154352-1, MHID: 0-07-154352-X. All trademarks are trademarks of their respective owners. Rather than put a trademark symbol after every occurrence of a trademarked name, we use names in an editorial fashion only, and to the benefit of the trademark owner, with no intention of infringement of the trademark. Where such designations appear in this book, they have been printed with initial caps. McGraw-Hill eBooks are available at special quantity discounts to use as premiums and sales promotions, or for use in corporate training programs. To contact a representative please e-mail us at [email protected]. TERMS OF USE This is a copyrighted work and The McGraw-Hill Companies, Inc. (“McGraw-Hill”) and its licensors reserve all rights in and to the work.
    [Show full text]
  • Analogue of Weil Representation for Abelian Schemes
    ANALOGUE OF WEIL REPRESENTATION FOR ABELIAN SCHEMES A. POLISHCHUK This paper is devoted to the construction of projective actions of certain arithmetic groups on the derived categories of coherent sheaves on abelian schemes over a normal base S. These actions are constructed by mimicking the construction of Weil in [27] of a projective representation of the symplectic group Sp(V ∗ ⊕ V ) on the space of smooth functions on the lagrangian subspace V . Namely, we replace the vector space V by an abelian scheme A/S, the dual vector space V ∗ by the dual abelian scheme Aˆ, and the space of functions on V by the (bounded) derived category of coherent sheaves on A which we denote by Db(A). The role of the standard symplectic form ∗ ∗ ∗ −1 ˆ 2 on V ⊕ V is played by the line bundle B = p14P ⊗ p23P on (A ×S A) where P is the normalized Poincar´ebundle on Aˆ× A. Thus, the symplectic group Sp(V ∗ ⊕ V ) is replaced by the group of automorphisms of Aˆ×S A preserving B. We denote the latter group by SL2(A) (in [20] the same group is denoted by Sp(Aˆ ×S A)). We construct an action of a central extension of certain ”congruenz-subgroup” Γ(A, 2) ⊂ SL2(A) b on D (A). More precisely, if we write an element of SL2(A) in the block form a11 a12 a21 a22! then the subgroup Γ(A, 2) is distinguished by the condition that elements a12 ∈ Hom(A, Aˆ) and a21 ∈ Hom(A,ˆ A) are divisible by 2.
    [Show full text]
  • Right Ideals of a Ring and Sublanguages of Science
    RIGHT IDEALS OF A RING AND SUBLANGUAGES OF SCIENCE Javier Arias Navarro Ph.D. In General Linguistics and Spanish Language http://www.javierarias.info/ Abstract Among Zellig Harris’s numerous contributions to linguistics his theory of the sublanguages of science probably ranks among the most underrated. However, not only has this theory led to some exhaustive and meaningful applications in the study of the grammar of immunology language and its changes over time, but it also illustrates the nature of mathematical relations between chunks or subsets of a grammar and the language as a whole. This becomes most clear when dealing with the connection between metalanguage and language, as well as when reflecting on operators. This paper tries to justify the claim that the sublanguages of science stand in a particular algebraic relation to the rest of the language they are embedded in, namely, that of right ideals in a ring. Keywords: Zellig Sabbetai Harris, Information Structure of Language, Sublanguages of Science, Ideal Numbers, Ernst Kummer, Ideals, Richard Dedekind, Ring Theory, Right Ideals, Emmy Noether, Order Theory, Marshall Harvey Stone. §1. Preliminary Word In recent work (Arias 2015)1 a line of research has been outlined in which the basic tenets underpinning the algebraic treatment of language are explored. The claim was there made that the concept of ideal in a ring could account for the structure of so- called sublanguages of science in a very precise way. The present text is based on that work, by exploring in some detail the consequences of such statement. §2. Introduction Zellig Harris (1909-1992) contributions to the field of linguistics were manifold and in many respects of utmost significance.
    [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]
  • From Arithmetic to Algebra
    From arithmetic to algebra Slightly edited version of a presentation at the University of Oregon, Eugene, OR February 20, 2009 H. Wu Why can’t our students achieve introductory algebra? This presentation specifically addresses only introductory alge- bra, which refers roughly to what is called Algebra I in the usual curriculum. Its main focus is on all students’ access to the truly basic part of algebra that an average citizen needs in the high- tech age. The content of the traditional Algebra II course is on the whole more technical and is designed for future STEM students. In place of Algebra II, future non-STEM would benefit more from a mathematics-culture course devoted, for example, to an understanding of probability and data, recently solved famous problems in mathematics, and history of mathematics. At least three reasons for students’ failure: (A) Arithmetic is about computation of specific numbers. Algebra is about what is true in general for all numbers, all whole numbers, all integers, etc. Going from the specific to the general is a giant conceptual leap. Students are not prepared by our curriculum for this leap. (B) They don’t get the foundational skills needed for algebra. (C) They are taught incorrect mathematics in algebra classes. Garbage in, garbage out. These are not independent statements. They are inter-related. Consider (A) and (B): The K–3 school math curriculum is mainly exploratory, and will be ignored in this presentation for simplicity. Grades 5–7 directly prepare students for algebra. Will focus on these grades. Here, abstract mathematics appears in the form of fractions, geometry, and especially negative fractions.
    [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]