Fragmentation of trees and drifted excursions
Vortrag von Dr. Paul Thévenin
Sprecher eingeladen von: Prof. Dr. Jean Bertoin
Datum: 19.10.22 Zeit: 17.15 - 18.15 Raum: ETH HG G 19.1
The fragmentation of a tree is a process which consists in cutting the tree at random points, thus splitting it into smaller connected components as time passes. In the case of the so-called Brownian tree, it turns out that the sizes of these subtrees, known as the Aldous-Pitman fragmentation process, have the same distribution as the lengths of the excursions over its current infimum of a linearly drifted Brownian excursion, as proved by Bertoin.
We provide a natural coupling between these two objects. To this end, we make use of the so-called cut-tree of the Brownian tree, which can be seen as the genealogical tree of the fragmentation process. Joint work with Igor Kortchemski.