##### Department of Mathematics,

University of California San Diego

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### Math 296 - Graduate Colloquium

## Jianfeng Lin

#### UCSD

## Rokhlin invariant, homology cobordism group and triangulation of manifolds

##### Abstract:

A triangulation of a topological space is a homeomorphism from this space to a simplicial complex. A famous problem in topology is whether all manifolds are triangulable. Surprisingly, the answer is no when dimension is at least 4. In this talk, I will explain the beautiful work of Galewski-Stern and Matumoto, which provides an obstruction theory for triangulating manifolds. I will also explain Manolescu's disproof of triangulation conjecture in all dimensions greater than 4.

### January 16, 2020

### 12:00 PM

### AP&M 6402

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