Lovász, László (ELTE) 

Graph limits meet Markov chains

 

To define the limit of a sequence of graphs which are neither dense nor very sparse is perhaps the most important question in graph limit theory. Several convergence notions have been proposed (Frenkl, Kunszenti-Kovács – Lovász – Szegedy, Backhausz – Szegedy), which interestingly lead to limit objects that can be viewed as (continuous space) Markov chains with some added features. In other words, the random walk ont he graph seems to be the key structure that carries over to the limit.

This observation motivates a goal to see how various results in graph theory carry over to these limit objects. We show that flow theory has a very natural and simple generalization. Counting subgraphs (for example, triangles) is another basic method in graph theory. A generalization of this to the Markov chain setting is not straightforward, but with Kunszenti-Kovács and Szegedy we could develop a theory that covers a good part of graph sequences with intermediate density.

 

The talk is held in English!

Az előadás nyelve angol!

Date: Nov 2, Tuesday 4:15pm

Place: BME, Building „Q”, Room QBF13

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