Speaker: Richard Chang

Title: Complexity of Group Membership and Iterated Product Problems on Groups Given as Multiplication Tables

This talk will cover much of the work of Barrington, Kadau, Lange, and McKenzie in "On the Complexity of Some Problems on Groups Input as Multiplication Tables." Specifically, I will discuss the complexity of testing properties of groups (abelianess, solvability, etc). Introduce the complexity class FO(log log n) of problems solvable by uniform poly-size circuit families of unbounded fan-in and depth O(log log n). I will show no problem in FOLL can be hard for L or for any other class containing PARITY. I will discuss the complexity of the CGM problem defined as given a group G as a multiplication table, a subset X of G, and a target element t, determining whether or not the subgroup generated by X contains t for various classes of groups (cylic, abelian, nilpotent). Additionally, I will discuss the complexity of the ITERATED PRODUCT problem for various classes of groups given as Cayley tables.