**Differences of Bijections**

**Daniel Velleman (Amherst/UVM) **

**October 28th, 4:00 PM, Votey 207**

Suppose G is an abelian group. Which functions from G to G can be written as a difference of two bijections? I will discuss theorems of Marshall Hall, Jr. and Laszlo Fuchs that answer this question, as well as some generalizations. This is joint work with Dan Ullman.