Commensurating actions of groups of birational transformations

Add to your list(s) Download to your calendar using vCal

• Yves de Cornulier (CNRS (Centre national de la recherche scientifique); Université Paris Saclay)
• Tuesday 16 May 2017, 11:00-12:00
• Seminar Room 2, Newton Institute.

If you have a question about this talk, please contact INI IT.

NPC - Non-positive curvature group actions and cohomology

A commensurating action is an action of a group on a set along with a subset that is commensurated, in the sense that it has finite symmetric difference with each of its translates. There are natural ways to go from commensurating actions to actions on CAT cube complexes and vice versa. For each variety X, we construct a natural commensurating action of the group of birational transformations of X. The commensurated subset turns out to be the set of irreducible hypersurfaces in X. Under the assumption that the acting group has Property FW (which means that every action on a CAT cube complex has a fixed point), we deduce restrictions on its birational actions.   (Joint work with Serge Cantat)

This talk is part of the Isaac Newton Institute Seminar Series series.

This talk is included in these lists:

• All CMS events
• Featured lists
• INI info aggregator
• Isaac Newton Institute Seminar Series
• School of Physical Sciences
• Seminar Room 2, Newton Institute
• bld31

Note that ex-directory lists are not shown.