Institut für Algebra, Zahlentheorie und Diskrete Mathematik Aktivitäten
Oberseminar Algebra, Zahlentheorie und Diskrete Mathematik

Oberseminar Algebra, Zahlentheorie und Diskrete Mathematik

Datum Vortragende/r Vortragstitel
Do 10.4.2025  

Vorbesprechung

Do 8.5.2025 Nils Wirries (LUH) Plesken Lie algebras of associative algebras with involution
Do 15.5.2025, 13:50

Loïs Faisant (IST Austria)

 

Counting rational curves with prescribed tangency conditions: a motivic analogue via universal torsors

Abstract: Given a smooth projective and geometrically irreducible curve C and a Mori Dream Space X, we present a general parametrisation of morphisms from C to X which allows us to express the Grothendieck motive of Hom (C,X) as a motivic function defined on some power of the scheme of effective divisors of C, generalising previous works of Bourqui. Such a parametrisation should be understood as lifting our morphisms to the universal torsor of X.
As an application, we prove a motivic analogue of a variant of Manin’s conjecture for Campana curves on smooth projective split toric varieties.

Do 15.5.2025, 15:10 Victor Wang (IST Austria)

Average sizes of mixed character sums

Abstract: In joint work with Max Xu, we prove that the average size of a certain smoothly weighted, mixed character sum of length x is on the order of sqrt(x), under a weak Diophantine genericity condition on the angle θ of the additive character e(nθ). Certain quadratic Diophantine equations play a key role. In contrast, it was proved by Harper that the average size is o(sqrt(x)) for rational θ. Some remaining open questions will be highlighted.

Mo 19.5.2025 in Göttingen

15:00 Maxim Gerspach (Göttingen)

16:30 Gunther Cornelissen (Utrecht)

Göttingen-Hannover Number Theory Workshop
Do 22.5.2025 Johannes Schmitt (Bochum)  
Do 5.6.2025    
Do 19.6.2025    
Do 26.6.2025    
Do 3.7.2025 Efthymios Sofos (Glasgow)  
Do 10.7.2025    
Mi 16.7.2025, 14:15 in G117 Marta Pieropan (Utrecht)