##### Department of Mathematics,

University of California San Diego

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### Math 292 - Topology seminar

## Rok Gregoric

#### UT Austin

## Moduli of oriented formal groups and cellular motivic spectra

##### Abstract:

The moduli stack of oriented formal groups embodies, in the world of spectral algebraic geometry, the fundamental chromatic connection between the stable homotopy category and formal groups. As such, it validates the folklore picture of Morava, Hopkins, et al. Somewhat surprisingly, it is also closely related to a more recent development: the "cofiber of $\tau$ philosophy" of Gheorghe-Isaksen-Wang-Xu.

In this talk, we will introduce the moduli stack of oriented formal groups, and explain how the algebro-geometric structure of its connective cover reflects and gives rise to the $\tau$-deformation structure of cellular motivic spectra over $\mathbb{C}$.

Host: Zhouli Xu

### April 12, 2022

### 1:00 PM

https://ucsd.zoom.us/j/99777474063

Research Areas

Geometry and Topology****************************