Algebraický seminář

Current seminar:
Monday, May 19, 2025, 3:40 - 4:40 pm, room K2 and via ZOOM
 

Sean Cox (VCU Richmond): The Flat Cover Conjecture in non-additive settings

Abstract: The proof of the Flat Cover Conjecture (FCC) about 25 years ago (Bican-El Bashir-Enochs, Eklof-Trlifaj) settled a longstanding question in the categories of modules. The FCC was subsequently proved in other settings, e.g., finitely accessible additive categories (Crivei-Prest-Torrecillas, Rosicky, Rump). But there are limits in non-additive settings, even for locally finitely presentable categories: Kruml proved, for example, that there is a countable monoid S such that the FCC fails in the category of all S-acts. We affirm a conjecture of Bailey and Renshaw by proving that the Flat Cover Conjecture does hold in the category of centered S-acts. A key tool is a new characterization of "cofibrant generation" of a class of monomorphisms.

Forthcomming:  
May 26 - Josef Svoboda (Caltech): TBA
June 9 - Thomas Peirce (Univ. Warwick): TBA
Previous program:

The Algebra Seminar was founded by Vladimir Korinek in the early 1950's and continued by Karel Drbohlav until 1981. The seminar resumed its activities in 1990 under the guidance of Jaroslav Jezek and Tomas Kepka. Since 1994, the seminar is headed by Jan Trlifaj.

Presently, the seminar is supported by GACR. It serves primarily as a platform for presentation of recent research of the visitors to the Department of Algebra as well as members of the Department and their students.