Colloquium

2020 Jan 23

Colloquium: Gil Kalai (HUJI) - Some recent advances in combinatorics

2:30pm to 3:30pm

Location: 

Manchester Building (Hall 2), Hebrew University Jerusalem
I will discuss some recent advances in combinatorics, among them the disproof of Hedetniemi conjecture by Shitov, the proof of the sensitivity conjecture by Huang, the progress on the Erdos-Rado sunflower conjecture by Alweiss, Lovett, Wu, and Zhang, and the progress on the expectation threshold conjecture by Frankston, Kahn, Narayanan, and Park.
2019 Dec 05

Colloquium: Yoel Groman (HUJI) - Floer homology of the magnetic cotangent bundle

2:30pm to 3:30pm

Location: 

Manchester Building (Hall 2), Hebrew University Jerusalem

Hamiltonian Floer cohomology was invented by A. Floer to prove the Arnold conjecture: a Hamiltonian diffemorphism of a closed symplectic manifold has at least as many periodic orbits as the sum of the Betti numbers. A variant called Symplectic cohomology was later defined for certain non compact manifolds, including the  cotangent bundle of an arbitrary closed smooth manifold. The latter is the setting for classical mechanics of constrained systems.

2020 Mar 19

Colloquium: CANCELLED

2:30pm to 3:30pm

Location: 

Manchester Building (Hall 2), Hebrew University Jerusalem

Abstract: A spanning tree of a graph G is a subgraph with the same vertex set which is a tree. In 1981, McKay proved an asymptotic result regarding the number of spanning trees in random k-regular graphs. In this talk we will discuss an analogous result for certain random simplicial complexes (All terms will be explained in the talk).
.
The talk is based on a joint work with Lior Tenenbaum.

Pages