Series: Penn State Logic Seminar

Date: Tuesday, September 12, 2000

Time: 2:30 - 3:20 PM

Place: 307 Boucke Building

Speaker: Stephen G. Simpson, Department of Mathematics, Penn State

Title: Undecidable Algebraic Theories, Part 1

Abstract: 

In this series of talks, I will show that each of the following
first-order theories is undecidable: the theory of graphs, the theory
of finite graphs, the theory of distributive lattices, the theory of
finite distributive lattices, the theory of commutative rings, the
theory of finite commutative rings, the theory of groups, the theory
of finite groups.  The proof will begin with an analysis of
computability in terms of hereditarily finite sets.