# Research Seminar Number Theory and Arithmetic Geometry

**Summer term 2024**

**Fridays, 10:45-11:45**

**Seminar room A410 in Welfenschloss (main building, Welfengarten 1) or online (researchseminars.org)**

Datum | Vortragende/r | Vortragstitel |
---|---|---|

Fr 19.4.2024 | ||

Fr 26.4.2024 | Guy Fowler (LUH) |
Pila's proof of André--Oort for C^n shows that the discriminants of the isolated special points on a hypersurface in C^n may be bounded by an ineffective constant that depends only on the degree of the hypersurface and the degree of its field of definition. In particular, the constant is independent of the height of the equation defining the hypersurface. Most of the special cases of André--Oort that are known effectively (due to Kühne, Bilu, Binyamini etc.) do not possess the same uniformity as Pila's ineffective result. In this talk, I will describe some results which are both uniform and effective for the family of hypersurfaces: a_1 x_1^m + ... + a_n x_n^m = b, where a_1, ..., a_n, b are rational and m is a positive integer. |

Fr 3.5.2024 | Christian Bernert (LUH) |
The Manin-Peyre conjecture predicts the distribution of points of bounded height on Fano varieties over number fields. I will report on joint work with Ulrich Derenthal where we study this conjecture in the case of del Pezzo surfaces of degree 5. |

Fr 10.5.2024 | ||

Fr 17.5.2024 | ||

Fr 31.5.2024 | ||

Fr 7.6.2024 | Ruida Di (LUH) | Uniform Bogomolov Conjecture for Tori |

Fr 14.6.2024 | ||

Fr 21.6.2024 | Cameron Wilson (Glasgow) |
Following work of Serre on the solubility of conics, a current problem of interest in the study of Diophantine equations is to count the number of varieties in families which have a rational point. In this talk I will give an overview of recent works in this area, before focussing on the particular example of diagonal quadric surfaces parameterised by {Y: wx=yz}. This family was first studied by Browning, Lyczak, and Sarapin, who showed that it exhibits an uncommonly large number of soluble members and attributed this phenomenon to the existence of thin sets on Y. They predicted that the “typical” behaviour should hold outside of these thin set, in the style of modern formulations of the Batyrev--Manin conjectures. In recent work I have shown that unusual behaviour occurs even with the removal of these thin sets by providing an asymptotic formula for the corresponding counting problem. Finally, I will outline the character sum methods used to prove this result and introduce an adaptation of the large sieve for quadratic characters. |

Fr 28.6.2024 | ||

Fr 5.7.2024 | ||

Fr 12.7.2024 |