##### Department of Mathematics,

University of California San Diego

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### Algebra

## Daniel S. Rogalski

#### MIT

## Projectively simple rings

##### Abstract:

Projectively simple rings are those positively graded rings which are as close to being simple as possible. We show that under suitable hypotheses, such rings can be described using constructions from algebraic geometry. This naturally leads to an interesting geometric question: which varieties have automorphisms which fix no proper subvarieties? This is joint work with James Zhang and Zinovy Reichstein.

Host: Lance Small

### November 15, 2004

### 2:00 PM

### AP&M 6438

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