Archiv aktualit
Online seminář z algebry - 12.11.2020 PDF Tisk

Další seminář z algebry se koná 12.11.2020 od 13.00 online na platformě ZOOM. Informace pro připojení a další program semináře je zde.

Marcos Mazari-Armida (Carnegie Mellon University)

Model-theoretic stability and superstability in classes of modules

Dividing lines in complete first-order theories were introduced by Shelah in the early seventies. A dividing line is a property such that the classes satisfying such a property have some nice behaviour while those not satisfying it have a bad one. Two of the best understood dividing lines are those of stability and superstability.
In this talk, I will study the notion of stability and superstability in abstract elementary classes of modules with respect to pure embeddings, i.e., classes of the form (K,≤p) where K is a class of R-modules for a  fixed ring R and ≤p is the pure submodule relation. In particular, using that the class of p-groups with pure embed- dings is a stable AEC, I  will present a solution to Problem 5.1 in page 181 of Abelian Groups by Laszlo Fuchs. Moreover, I will show how the notion of superstability can be used to give new characterizations of noetherian rings, pure-semisimple rings, and perfect rings.

Aktualizováno Úterý, 10 Listopad 2020 15:17
Online seminář z diferenciální geometrie - 9.11.2020 PDF Tisk

Seminář z diferenciální geometrie pokračuje 9.11.2020 od 10:00 online na platformě MS Teams

Připojení ke schůzce ZDE.

Andrei Dikarev (ÚMS):

On holonomy of Weyl connections in Lorentzian signature

I will present my recent results about the classification of the holonomy algebras of Weyl connections in Lorentzian signature. A  special attention will be paid to the construction of examples of Weyl connections with different holonomy algebras.

Aktualizováno Pátek, 30 Říjen 2020 15:58