# Math 521A: Abstract Algebra

Course number: 21641
Fall 2008
MWF, 10:00 -11:50.
GMCS 328
San Diego State University
Final Exam: Fri. Dec. 19, 08:00-10:00

Professor: Mike O'Sullivan
Email: m.osullivan@math.sdsu.edu
Office: GMCS #579, 594-6697
Office Hours: MWF 8-9, MW 1-2,
You may also make an appointment for another time or stop by my office. If I am in and available, we can talk.

## Text

Hungerford, Abstract Algebra: An Introduction 2nd ed.
Review for the first exam.
Review for the second exam.
Review for the third exam.
Review for the final exam.

## Course Description

We are using a well written text book in this course. It takes an unusual approach to the subject, starting with structures that you know well--the integers and polynomials--then developing the more general theory of rings before introducing groups. The author organizes the material to emphasize central themes in abstract algebra: divisibility, the notion of congruence, the creation of new algebraic structures from known ones and homomorphims (functions that preserve structure). Chapters 1 and 2 discuss these notions for the integers; Chapters 4 and 5 discuss them for polynomial rings. Chapters 3, and 6 develop the same ideas for general rings. Chapter 7 is a new beginning, introducing the more general and abstract theory of groups. We will only cover the first few sections of this chapter.

## Prerequisites

The main prerequisite is Discrete Mathematics, Math 245. It will be worthwhile to review the fundamentals of logic ("and", "or", "implies", "for all", "there exists", and negation). We will use a variety of proof methods in this course: direct proof, proof by contradiction, and mathematical induction. We use equivalence relations.

## Schedule

Here is a rough idea of the amount of time I expect to spend on each topic.

 SECTIONS TOPICS TIME Ch. 1,2 The integers: divisibility, primality. Congruence classes and arithmetic, the rings Z_m 3 weeks Ch, 3 General rings, and homorphisms 3 weeks Ch. 4 Polynomial rings, divisibility and irreducibility. 3 weeks Ch. 5 Congruence classes and arithmetic in polynomial rings. 1 week Ch. 6 Congruences classes and arithmetic for general rings. 2 weeks §7.1-5 Groups. 3 weeks