The Bielefeld Algebraic and Arithmetic Geometry Seminar 2024/2025

Welcome to the website of the Bielefeld Algebraic and Arithmetic Geometry Seminar! For more information, please contact one of the organizers: Claudia Alfes, Ana Botero, Eike Lau, Michael Spiess, Charles Vial, and Thomas Zink.

Talks

Wednesday 23 October, 2024
14:15	V2 210/216	Danylo Radchenko (U Lille) Fourier uniqueness pairs, interpolation formulas, and modular forms [Abstract] A Fourier uniqueness pair is a pair of subsets A, B of Euclidean space such that any function can be reconstructed from its values on A and the values of its Fourier transform on B. I will give an overview of recent constructions of Fourier uniqueness pairs, with an emphasis on explicit constructions using modular forms, and discuss their application in the sphere packing and energy minimization problems.
15:45	V2 210/216	Franco Rota (Glasgow) Towards Homological Mirror Symmetry for log Del Pezzo surfaces [Abstract] The homological mirror symmetry conjecture predicts a duality, expressed in terms of categorical equivalences, between the complex (or symplectic) geometry of a variety X and the symplectic (or complex) geometry of its mirror object Y. Motivated by this, we study a series of singular surfaces called log del Pezzo. I will describe the derived category of a series of log del Pezzo’s, using the McKay correspondence and explicit birational geometry. Then, I’ll mention early mirror results, focusing mostly on the special case of smooth low degree del Pezzo surfaces. For these, we will compare several mirror constructions using the language of pseudolattices. This is joint work with Giulia Gugiatti.
Wednesday 6 November, 2024
14:15	V2 210/216	Markus Kirschmer (Bielefeld) TBD [Abstract] TBD
15:45	V2 210/216	Florian Breuer (Newcastle) Heights of modular polynomials [Abstract] For every positive integer $N$, the modular polynomial $\Phi_N(X,Y)$ has integer coefficients and vanishes precisely at pairs of $j$-invariants of elliptic curves linked by a cyclic isogeny of order $N$. These polynomials have applications in cryptography and define integral (but singular) models for the modular curves $X_0(N)$. Their coefficients grow rapidly with $N$. In this talk, I will explain recent joint work with Fabien Pazuki and Desir\'ee Gij\'on G\'omez obtaining explicit upper and lower bounds on the size of these coefficients. Our methods also lead to explicit bounds on the heights of Hecke images. If time allows, I can also outline analogous results for Drinfeld modular polynomials.
Wednesday 13 November, 2024
14:15	V2 210/216	Robin de Jong (Leiden) TBD [Abstract] TBD
15:45	V2 210/216	Francesco Denisi (Paris Cite) TBD [Abstract] TBD
Wednesday 20 November, 2024
14:00	V2 210/216	Johannes Krah (Bielefeld) Phantoms and exceptional collections on rational surfaces [Abstract] TBD
16:30	V2 210/216	Alexander Kuznetsov TBD [Abstract] TBD
Wednesday 27 November, 2024
14:15	V2 210/216	Jan-Willem van Ittersum (Cologne University) TBD [Abstract] TBD
15:45	V2 210/216	David Ter-Borch Gram Lilienfeldt (Universität Leiden) TBD [Abstract] TBD
Wednesday December 11, 2024
14:15	V2 210/216	Martin Raum (Chalmers) TBD [Abstract] TBD
15:45	V2 210/216	Rızacan Çiloğlu (TU Darmstadt) TBD [Abstract] TBD
Wednesday 15 January, 2025
14:15	V2 210/216	Sebastián Herrero (University of Santiago de Chile/ETH Zurich) TBD [Abstract] TBD
15:45	V2 210/216	Robert Laterveer (Strasbourg) TBD [Abstract] TBD
Wednesday 29 January, 2025
14:15	V2 210/216	Giada Grossi (Universite Sorbonne Paris Nord) TBD [Abstract] TBD
15:45	V2 210/216	Josefien Kuijper (Utrecht) TBD [Abstract] TBD

Navigation

Information

Seminars

Conference

The Bielefeld Algebraic and Arithmetic Geometry Seminar 2024/2025

Talks

Wednesday

23 October, 2024

Wednesday

6 November, 2024

Wednesday

13 November, 2024

Wednesday

20 November, 2024

Wednesday

27 November, 2024

Wednesday

December 11, 2024

Wednesday

15 January, 2025

Wednesday

29 January, 2025