##### Department of Mathematics,

University of California San Diego

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### String Theory and Geometry

## Paul Aspinwall

#### Duke University

## Superpotentials for D-branes and A-infinity algebras

##### Abstract:

Worldvolumes of $D$-branes on Calabi-Yau threefolds give rise to supersymmetric gauge theories. If the $D$-brane is marginally stable these theories are quiver gauge theories. Using the derived category of coherent sheaves to analyze such $D$-branes, the superpotential of these gauge theories may be determined systematically.

Host: Mark Gross

### November 9, 2004

### 2:00 PM

### AP&M 5829

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