##### Department of Mathematics,

University of California San Diego

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### Math 290B - Toplogy Colloquium

## Gerd Laures

#### University of Bochum, Germany

## The signature is an E-infinity ring mapThe signature can be regarded as a map from oriented topological bordism

##### Abstract:

The signature can be regarded as a map from oriented topological bordism to symmetric L theory. We investigate its multiplicative properties and show that there is simplicial model for the signature which is a map of E symmetric ring spectra. The construction generalizes to a large class of theories which are bordism-like in a suitable sense. The work is joint with James McClure.

Host: Nitya Kitchloo

### April 17, 2006

### 2:00 PM

### AP&M 5218

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