We are resuming the colloquium with the start of the new semester. 

Next week, we have the pleasure of having Prof. Gil Cohen give a talk in the colloquium.

The seminar will be held on Monday, May 6th at 14:00.

Location: C220.

The title, abstract and bio appear below.

Looking forward to seeing you,

Sagie and Liat

Tight Bounds for the Zig-Zag Product

In this talk, we will explore the Zig-Zag product, a pivotal concept in pseudorandomness introduced over two decades ago by Reingold, Vadhan, and Wigderson. We will utilize methods from free probability theory and analytic combinatorics to establish a tight bound on the spectral expansion when Zig-Zag-ing with a (vertex-transitive) graph H. Our bound incorporates H's entire spectrum, deviating from the classical, combinatorial, bound.

This talk is designed for a broad audience; no prior knowledge of free probability, analytic combinatorics, or expanders for that matter, is required.

This work is a collaboration with Itay Cohen and Gal Maor.

Bio:

Gil Cohen is a faculty member at the Department of Computer Science at Tel Aviv University. He is working on pseudo-randomness and derandomization, explicit constructions, and coding theory. Of particular interest are randomness extractors, derandomization of space-bounded computation, spectral graph theory, tree codes, locally decodable codes, and algebraic-geometric codes.