GeCo GeDi Seminarshttps://gecogedi.dimai.unifi.it/seminars/en-usMon, 16 Sep 2019 04:07:37 +0000Homogeneous Einstein metrics on Euclidean spaceshttps://gecogedi.dimai.unifi.it/seminar/1324/2019-09-17: C. Böhm.<p>We show that homogeneous Einstein metrics on Euclidean spaces are Einstein solvmanifolds, using that they admit periodic, integrally minimal foliations by homogeneous hypersurfaces. For the geometric flow induced by the orbit-Einstein condition, we construct a Lyapunov function based on curvature estimates which come from real GIT.</p>https://gecogedi.dimai.unifi.it/seminar/1324/Categorification and cohomological Hall algebrashttps://gecogedi.dimai.unifi.it/seminar/1325/2019-09-20: F. Sala.<p>Let M denote the moduli stack of either coherent sheaves on a smooth projective surface or Higgs sheaves on a smooth projective curve X. The convolution algebra structure on the Borel-Moore homology of M is an instance of two-dimensional cohomological Hall algebras. These examples were defined by Kapranov-Vasserot and by Schiffmann and me, respectively.During the first part of the talk, I will give a gentle introduction to cohomological Hall algebras and their relevance in algebraic geometry and representation theory. The second part of the talk is devoted to the description of the full categorification of the cohomological Hall algebra of M. I will explain the construction and some applications in the theory of moduli spaces of sheaves. This is based on a joint work with Mauro Porta.</p>https://gecogedi.dimai.unifi.it/seminar/1325/Gruppi di automorfismi e Geometria Complessa Ellitticahttps://gecogedi.dimai.unifi.it/seminar/1322/2019-09-26: R. Ugolini.https://gecogedi.dimai.unifi.it/seminar/1322/Invariant translators in some Thurston geometrieshttps://gecogedi.dimai.unifi.it/seminar/1323/2019-10-03: G. Pipoli.<p>Translating solutions to the mean curvature flow are special hypersurfaces that evolve under mean curvature flow preserving their shape and translating along a fixed direction. They have a crucial role in understanding the singularities of the flow and provide interesting explicit examples of solutions. In this talk we discuss the classification of translating surfaces in the Heisenberg and Solvable groups that are invariant under the action of a one-parameter group of isometries of the ambient space. In particular we highlight similarities and differences with the analogous examples in the Euclidean space.</p>https://gecogedi.dimai.unifi.it/seminar/1323/TBAhttps://gecogedi.dimai.unifi.it/seminar/1328/2019-11-14: R. Piovani.https://gecogedi.dimai.unifi.it/seminar/1328/TBAhttps://gecogedi.dimai.unifi.it/seminar/1326/2019-12-05: Z. Sjöström Dyrefelt.https://gecogedi.dimai.unifi.it/seminar/1326/