Τετάρτη 6 Νοεμβρίου 2019, 13:00, Αίθουσα Γ31

Ομιλητής: Romain Tessera, Institute Mathématiques de Jussieu, Paris Diderot (Paris 7)

Τίτλος Ομιλίας : "Quantitative measure equivalence between discrete groups"

Περίληψη

Two groups are measure equivalent if they both admit measure-preserving
actions on a measured space, such that the two actions commute and have
finite
measure fundamental domains. The archetype of measure equivalent groups
are pairs of lattices in a same locally compact group. A celebrated
theorem of Orstein and Weiss says that all infinite countable amenable
groups are measure equivalent. In a recent work, we study quantitative
versions of measure equivalence, where an integrability condition is
imposed on the measured coupling.