MONDAY, November 21, 2005

GEOMETRY/TOPOLOGY SEMINAR 667

TIME: 12:20 p.m. - 1:20 p.m.
ROOM: 209A Ayres Hall
SPEAKER: Dr. Valeriy Berestovskiy, Visiting Faculty
TITLE: Curvature tensor of Riemannian manifold II

UNDERGRADUATE HONORS SEMINAR

TIME: 12:20 p.m.
ROOM: 301 Ayres Hall
SPEAKER: Jordan C. Schettler
TITLE: Lehmer’s Totient Problem and Carmichael Numbers in a PID (Part I)
ABSTRACT: Lehmer's totient problem consists of determining the set of positive integers n such that phi(n)|n - 1 where phi is Euler's totient function. It is not obvious whether there are any composite n satisfying this divisibility condition; in fact, any such composite n is a Carmichael number (although every known Carmichael number doesn't actually have this property). We will generalize the above divisibility condition (with the cardinality [when finite] of the group of units in a quotient ring playing the role of phi) as well as a reasonable notion of Carmichael numbers in a PID R, and use a pair of handy short exact sequences to show how similar statements to those above follow in more generality while picking up a couple of generalizations for a classical identities involving phi along the way. Included will be a generalization of the work of Korselt and an extension of the work of Alford, Granville and Pomerance.

FIRST-YEAR GTA TEACHING SEMINAR

TIME: 3:35 p.m. - 4:50 p.m.
ROOM: 309B Ayres Hall
SPEAKER: Dr. Amy Szczepanski
TITLE: “What do the scores on your students’ tests mean?”
ABSTRACT: What to do when you're grading the exam and you realize that the scores are going to be just terrible? We will discuss reasons behind low exam scores -- from poor student comprehension to overly difficult exams -- and identify strategies for ensuring that exams are fair and accurate assessments of student knowledge. Please read case study 14 ("What were they thinking?") from Friedberg before this session.

DIFFERENTIAL EQUATIONS/APPLIED MATH & COMPUTATIONAL SCIENCE SEMINAR

TIME: 4:30 p.m.
ROOM: 104 Ayres Hall
SPEAKER: Tim Clayton
TITLE: Optimal Control of a chemotaxis system

SPEAKER: George Butler
TITLE: Bounds on Error Correcting Codes


WEDNESDAY, November 23, 2005

UNDERGRADUATE HONORS SEMINAR

TIME: 12:20 p.m.
ROOM: 301 Ayres Hall
SPEAKER: Jordan C. Schettler
TITLE: Lehmer’s Totient Problem and Carmichael Numbers in a PID (Part II)