## 2014

### Intercity Number Theory Seminar

14 February, Leiden. Room 412 of the Snellius (math institute). Followed by the oratie of Joost Batenburg.- 11:00–12:00
- Wouter Zomervrucht Leiden, Descent of genus 1 curves
In December 2020, Peter Scholze posed a challenge to formally verify the main theorem on liquid ℝ-vector spaces, which is part of his joint work with Dustin Clausen on condensed mathematics. I took up this challenge with a team of mathematicians to verify the theorem in the Lean proof assistant. Half a year later, we reached a major milestone, and our expectation is that shortly we will have completed the full challenge. In this talk I will give a brief motivation for condensed/liquid mathematics, a demonstration of the Lean proof assistant, and discuss our experiences formalizing state-of-the-art research in mathematics.
- 13:00–14:00
- David Holmes Leiden, Ranks of twists of elliptic curves and rational points on Kummer varieties
In December 2020, Peter Scholze posed a challenge to formally verify the main theorem on liquid ℝ-vector spaces, which is part of his joint work with Dustin Clausen on condensed mathematics. I took up this challenge with a team of mathematicians to verify the theorem in the Lean proof assistant. Half a year later, we reached a major milestone, and our expectation is that shortly we will have completed the full challenge. In this talk I will give a brief motivation for condensed/liquid mathematics, a demonstration of the Lean proof assistant, and discuss our experiences formalizing state-of-the-art research in mathematics.
- 14:15–15:15
- Michiel Kosters Leiden, Images of maps between curves over a large field
In December 2020, Peter Scholze posed a challenge to formally verify the main theorem on liquid ℝ-vector spaces, which is part of his joint work with Dustin Clausen on condensed mathematics. I took up this challenge with a team of mathematicians to verify the theorem in the Lean proof assistant. Half a year later, we reached a major milestone, and our expectation is that shortly we will have completed the full challenge. In this talk I will give a brief motivation for condensed/liquid mathematics, a demonstration of the Lean proof assistant, and discuss our experiences formalizing state-of-the-art research in mathematics.

### Intercity Number Theory Seminar

28 February, Groningen. Room 267 in Bernoulliborg.- 12:00–13:00
- Jan Steffen Müller Oldenburg, A
*p*-adic BSD conjecture for modular abelian varieties - 13:45–14:45
- Masato Kuwata Chuo University, Elliptic K3 surfaces with Mordell-Weil rank 18
- 15:00–16:00
- Moritz Minzlaff, Three and a half results on p-adic point counting and beyond
- 16:15–17:15
- Sietse Ringers Groningen, Deformation quantization of Poisson manifolds à la Kontsevich

### Intercity Number Theory Seminar

28 March, Eindhoven. At the occasion of the*afscheidsrede*of Arjeh Cohen. The first four lectures are in Auditorium 7.

- 11:30–12:20
- Willem de Graaf Trento, Unit groups of integral abelian group rings
- 13:00–13:50
- Daan Krammer Warwick, The braid group of
**Z**^{n} - 13:50–14:40
- Jean-Pierre Tignol Louvain, Triality and compositions
- 14:50–15:40
- Stefan Maubach Bremen, The profinite polynomial endomorphisms and the profinite polynomial automorphism group
- 16:00–17:00
- Arjeh Cohen Eindhoven, Wiskunde in het Web

### Intercity Number Theory Seminar

25 April, VU Amsterdam. Room M655 of the W&N building.- 13:30–14:30
- Nuno Freitas Bayreuth, An asymptotic Fermat Last Theorem for totally real fields
- 15:00–16:00
- Hang Liu VU Amsterdam, On the K_2 of certain families of curves
- 16:15–17:15
- Lenny Taelman Leiden, Characteristic classes of genus one curves

### 6th Belgian-Dutch Algebraic Geometry Day

16 May, Leuven. Celestijnenlaan 200, Room A00.225. See also this page.- 14:00–15:00
- Olivier Benoist Strasbourg, Complete families of smooth space curves
- 15:10–16:10
- Frank-Olaf Schreyer Saarbrücken, Matrix factorizations and families of curves of genus 15
- 16:40–17:40
- Carel Faber Utrecht, On the cohomology of the moduli spaces of pointed curves of genus three

### RISC/Intercity Number Theory Seminar

23 May, CWI Amsterdam. Lectures are in room L120.- 13:00–13:45
- Serge Fehr CWI, Reconstructing a Shared Secret in the Presence of Faulty Shares - A Survey
- 14:00–14:45
- Aner Moshe Ben Efraim Ben-Gurion, Multi-Linear Secret-Sharing Schemes
- 15:15–16:00
- Ronald Cramer CWI/Leiden, Optimal Algebraic Manipulation Detection Codes
- 16:15–17:00
- Daniele Venturi Roma 1, Non-Malleable Codes and Applications

### RISC Seminar/Intercity Number Theory Seminar

19 September, KNAW Amsterdam. This day is part of the RISC Seminar on the Theory of Cryptography (September 18-19), which takes place in the Tinbergenzaal of the Trippenhuis. Registering is free, but required, also for those coming only on Friday (deadline September 12). Lunch will be provided on Friday. See the webpage for more information, including the program.### Intercity Seminar Number Theory, "Algebraic groups and number theory"

17 October, Utrecht. Buys Ballot Building, room 061 (note: due to construction works, you can no longer get to this building by walking through the Minnaert building, you have to walk around it and enter from Princetonplein).- 13:00–14:00
- Jan Draisma, Euclidean distance degrees of homogeneous varieties
- 14:00–15:00
- Valentijn Karemaker, Hecke algebra isomorphisms and adelic points on algebraic groups
- 15:30–16:30
- Roland Lötscher, Essential dimension of gerbes
- 16:30–17:30
- Nikita Karpenko, A numerical invariant for linear representations of finite groups

### Intercity Seminar Number Theory

31 October, Leiden. Morning in room Snellius B1, afternoon in 312- 11:30–12:30
- Fabien Pazuki, Bad reduction of curves with CM jacobians
- 13:30–14:30
- Marco Streng, Modular units and elliptic divisibility sequences
- 15:00–16:00
- Benjamin Matschke, Solving S-unit and Mordell equations via Shimura-Taniyama conjecture
- 16:15–17:15
- Martin Bright, The Brauer-Manin obstruction and reduction mod p

### 7th Belgian-Dutch Algebraic Geometry Day

14 November, UvA Amsterdam. Science Park 904. First lecture in C1.110, second and third in C0.110. See also this page.- 13:30–14:30
- Minhyong Kim Oxford, Non-abelian reciprocity laws and Diophantine geometry
- 15:00–16:00
- Mingmin Shen UvA, Multiplicative Chow-Künneth decompositions
- 16:30–17:30
- Jakob Stix Frankfurt, Gorenstein orders and abelian varieties over finite fields