Tuesday, 4 November
04:15 pm
Bielefeld University S1-500
Künstliche Intelligenz und AI Agenten bei Schüco
Speaker: Lukas Wresch
Orientierende Praxisstudien
Tba
Wednesday, 5 November
02:15 pm
Bielefeld University H15
Derived equivalence of hyperkahler fourfolds
Speaker: Grzegorz Kapustka
Algebraic and Arithmetic Geometry
We present conditions under which two K3^[2] type manifolds are derived equivalent.
03:45 pm
Bielefeld University H15
Periods of double EPW sextics and double EPW cubes
Speaker: Michał Kapustka
Algebraic and Arithmetic Geometry
Double EPW sextics and double EPW cubes are two families of polarised hyperkaehler manifolds arising from the same data, namely Lagrangian subspaces in the third exterior power of a six dimensional vector space. We will discuss relations between Hodge structures of pairs of these manifolds corresponding to the same Lagrangian subspace.
As a consequence we shall describe both compared varieties as moduli spaces of objects on the same K3 category: the Kuznetsov component of an associated Gushel-Mukai fourfold. This is joint work with G. Kapustka, A. Kuznetsov, G. Mongardi.
Friday, 7 November
01:15 pm
Bielefeld University U2-232
Algebras, quivers and species in fusion and tensor categories
Speaker: Mateusz Stroinski
Seminar Representation Theory of Algebras
By results of Etingof and Ostrik, the theory of module categories over a finite tensor category C is equivalent to that of modules over algebras inside C. Hence it is a generalisation of the representation theory of finite-dimensional algebras, internal to C.
The aim of this talk is to build on this observation: I will explain how to define Jacobson radicals, quivers, species and their representations, all internal to C.
Applications I will present include a proof of a conjecture of Etingof-Ostrik on (semi)simple algebras in C, based on joint work with Kevin Coulembier (University of Sydney) and Tony Zorman (TU Dresden), as well as a variant of Gabriel's theorem on basic Morita representatives given by species in C, based on an ongoing collaboration with Edmund Heng (University of Sydney).
03:00 pm
Bielefeld University Hörsaalgebäude Y
Die Welt in der Welt: p-adische Poetiken in Syzygie
Speaker: Oswald Egger
Ars Mathematica Vorlesung
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05:00 pm
Bielefeld University Hörsaalgebäude Y
Condensed mathematics
Speaker: Peter Scholze
Ars Mathematica Vorlesung
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Thursday, 27 November
04:15 pm
Bielefeld University V2-210/216
Zeros of S-characters - Showcasing the Computer Algebra System OSCAR
Speaker: Michael Joswig
Mathematisches Kolloquium (TRR 358)
The concept of $S$-characters of finite groups was introduced by Zhmud' (1995) as a generalization of transitive permutation characters. Any non-trivial $S$-character takes a zero value on some group element. By a deep result depending on the classification of finite simple groups a non-trivial transitive permutation character even vanishes on some element of prime power order. J-P. Serre asked whether this generalizes to $S$-characters. We provide a translation of this question into the language of polyhedral geometry and thereby construct many counterexamples, using the capabilities of the computer algebra system OSCAR.
The work on S-characters is joint with Thomas Breuer und Gunter Malle. OSCAR is joint work with The OSCAR Development Team, currently lead jointly with Simon Brandhorst, Claus Fieker, Tommy Hofmann and Max Horn