##### Department of Mathematics,

University of California San Diego

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### Algebra Colloquium

## Daniel Krashen

#### Yale University

## Geometry and division algebras

##### Abstract:

In this talk I will introduce the study of finite dimensional division algebras and the Brauer group, and I will discuss the fundamental problem of computing the index of a Brauer class. It turns out that algebraic geometry can play an important role in this problem. In particular I will describe the theory of twisted sheaves and how it allows one to solve this problem in certain cases.

Host: Adrian Wadsworth

### January 22, 2007

### 2:00 PM

### AP&M 6402

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