Activities This Week
Arithmetic applications of o-minimality
Étale descent and definabilization (cont.) Online
Jun 1, 10:10—12:00, 2021, online
Speaker
Moshe Kamensky (BGU)
Jerusalem - Be'er Sheva Algebraic Geometry Seminar
Grothendieck period conjecture and 1-motives
Jun 2, 15:00—16:30, 2021,
Speaker
Cristiana Bertolin (Torino)
Abstract
We start computing the periods and the dimension of the motivic Galois group of 1-motives. Then we apply Grothendieck period conjecture to 1-motives and we will see some consequences of this conjecture.
BGU Probability and Ergodic Theory (PET) seminar
Slow entropy of higher rank abelian unipotent actions Online
Jun 3, 11:10—12:00, 2021, Online
Speaker
Daren Wei (The Hebrew University)
Abstract
We study slow entropy invariants for abelian unipotent actions U on any finite volume homogeneous space $G/\Gamma$. For every such action we show that the topological complexity can be computed directly from the dimension of a special decomposition of Lie(G) induced by Lie(U). Moreover, we are able to show that the metric complexity of the action coincides with its topological complexity, which provides a classification of these actions in isomorphic class. As a corollary, we obtain that the complexity of any abelian horocyclic action is only related to the dimension of G. This generalizes our previous rank one results from to higher rank abelian actions. This is a joint work with Adam Kanigowski, Philipp Kunde and Kurt Vinhage.