Jen Paulhus, Ph.D.

Foundations of Abstract Algebra

email: paulhus@math.grinnell.edu     pgp key
Office Hours:
    Monday and Friday: 10:30-11:30 AM
    Tuesday 3:30-4:30 PM
    Thursday 9:30-10:30 AM
Office: 2519 Noyce Science Center

Text: Abstract Algebra: A First Course, 2nd edition, Dan Saracino
Material Covered: Chapters 1-21, I assume you are familiar with the material in Chapter 0

Abstract algebra is one of the fundamental branches of modern mathematics. While it has its roots as far back as the late 1700's, it first came to prominence in the early 1900's. There are many current active areas of research in algebra, and the underpinnings of internet security come from algebra. This course will introduce you to several of the primary object of study in the subject: groups, rings, and fields.

Syllabus
2nd Half Updates

Homework

Daily Topics

Class Date Pages Section(s) Covered Words
Jan. 22 10-14, 16-19 1, 2 : Intro to Groups binary operation, group, identity, inverse, general linear group of degree 2
Jan. 24 25-30, 34 3 : Basic Properties of Groups abelian group, order of a group
Jan. 27 4, 6-7, 20-21, 35- 37 0, 2, 4 : Integers a divides b, prime, greatest common divisor, relatively prime, least common multiple (see exercise 4.31)
Jan. 29 33-34,38 4 : Order of an Element order of an element, element of finite order, element of infinite order
Jan. 31 39-40 4 : Cyclic Groups cyclic group, generator of a group
Feb. 3 notes*, 74-76 8, Problem #8.15 : Dihedral Group plane symmetry, regular polygon, dihedral group of order 2n (all on attached notes)
Feb. 5 43-50 5: Subgroups subgroup, proper subgroup, trivial subgroup, subgroup lattice
Feb. 7 50-52, 59-62 5, 7: Cyclic Subgroups / Functions function, onto, one-to-one, domain, range, bijection, inverse function
Feb. 10 63-64, 66-69 8 : Symmetric Groups cycles, disjoint cycles, symmetric group on X, transposition
Feb. 12 70-73 8 : Alternating Group even permutation, odd permutation, alternating group of degree n
Feb. 14 81-83 9: Equivalence Relations and Z/nZ equivalence relation, equivalence class
Feb. 17 21-22 2: Z/nZ, U(n) remainder of a mod n, congruent modulo n, additive group of integers mod n
Feb. 19 83-85 9: Cosets right coset of H in G, left coset
Feb. 21 83-85, 88-91 9, 10 : Cosets, Lagrange's Theorem Lagrange's Theorem, cardinality, index, coset representative (see 82)
Feb. 24 92,103-104 (assuming abelian) 11 : Quotient Group quotient of abelian groups
Feb. 26 99-102 11: Normal Subgroups, Quotient Groups normal subgroups, quotient groups
Feb. 28 103-105, 55-57 11 : Cauchy's Theorem and other Consequences
Mar. 2 55-57, 109-113 6,12 : Direct Product, Homomorphisms direct product, homomorphism, isomorphism, monomorphism, epimorphism, automorphism
Mar. 4 Exam 1 1-5, 7-10
Mar. 6 114-115, 121-122 12, 13 : Homomorphism Properties inverse image, homomorphic image
Mar. 9 122-124, 127 13: Isomorphism Theorems kernel, fundamental theorem on gp homomorphisms,
Mar. 11 125-126, 128-130, 153-154 13, 16 : Isom. Theorems, Rings second and third isomorphism theorems, ring, commutative ring, unity
Mar. 13 155-160 16: Ring Properties, Integral Domains zero divisor, unit , nilpotent, trivial ring, integral domain, division ring, field
Mar. 30/31 164-170 17: Subrings, Ideals, Prime Ideals subring, ideal, proper ideal, trivial ideal, principal ideal generated by a
Apr. 1/2 171-182 17: Maximal Ideals, 18: Ring Homomorphisms ring homomorphisms, canonical homomorphism, characteristic 0, characteristic p
Apr. 6/7 183-193 18: Quotient Fields quotient field of an integral domain, extension, polynomial rings, leading coefficient, constant polynomial
Apr. 8/9 194-198 19: Factoring root, irreducible, primitive
Apr. 13/14 199-201 19: Irreducibility Tests Gauss' Lemma, Eisenstein's Criterion, mod p Irreducibility (Thm 19.12)
Apr. 15/16 205-207 20: Ideals in Polynomial Rings recap prinicpal ideals and maximal ideals
Apr. 20/21 211-212, 217-218, 220-221 21: Principal Ideal Domain prime, irreducible, associates, principal ideal domain, Euclidean domain
Apr. 22/23 -- Flexible Day/Exam Prep
Apr. 24 Exam 2 [instructions] 6, 11-13, 16-19
Apr. 27/28 213-216, 218-220 21: Unique Factorization Domain unique factorization domains
Apr. 29/30 93-94, 98 (10.32), Notes on Pweb: 133-139 Introduction to Group Actions centralizer, conjugacy classes, group acting on a set, orbit, stabilizer, not in book: faithful action, kernel, transitive action
May 4/5 95, Notes on PWeb: 140-144 The Class Equation and Consequences
May 6/7 Notes on PWeb: 144-148 Simplicity of A5
* Dihedral Notes

Homework Assignments

Make sure you are familiar with the Grading Policies and Rubric for the class. Homework solutions will be posted on Pweb. Homework is due by the time class starts, unless you LaTeX the solutions and are in class on time the day the homework is due. Then it should be submitted on PWeb by 7 PM that day.

HW Due Date Problems
# 0 Jan. 24 Email me with answers from class 1/22, and read syllabus
# 1 Jan. 31 [pdf]
# 2 Feb. 7 [pdf]
# 3 Feb. 14 [pdf]
# 4 Feb. 21 [pdf]
# 5 Feb. 28 [pdf] (last updated: 2/25)
# 6 Mar. 13 Mar. 18 [pdf]
# 7 Apr. 3 [pdf]
# 8 Apr. 10 [pdf]
# 9 Apr. 17 [pdf]
# 10 May 1 [pdf]
#11 May 8 [pdf]