Number Theory Web Seminar

This number theory seminar is purely online. Our talks come from various corners of the field and of the world. They are streamed live on Zoom.

Organizers:


There are no fees, but registration is necessary. To register please follow this link.

Registered users will receive an email a few hours before the talk with a link to the Zoom meeting. 

The seminar runs every Thursday. Please note the usual times of the seminar below and in the FAQ Section. 

Talks are usually 50 minutes and then time for some questions.

Contact: ntweb.seminar@gmail.com

YouTube Channel: https://www.youtube.com/@numbertheorywebseminar 

Please consider the following:

Next talk:



Julia Stadlmann, Primes in arithmetic progressions to smooth moduli
(Stanford University) 

Thursday, January 16, 2025 (8am PST, 11am EST, 4pm GMT, 5pm CET, 6pm Israel Standard Time, 9:30pm Indian Standard Time)
Friday, January 17, 2025 (12am CST, 3am AEDT, 5am NZDT)

Abstract: For large x and coprime a and q, the arithmetic progression n = a mod q contains approximately pi(x)/phi(q) primes up to x. For which moduli q can we prove that this approximation has small error terms? In this talk, I will focus on results for smooth moduli, which were a key ingredient in Zhang's proof of bounded gaps between primes and later improvements of Polymath. Following arguments of the Polymath project, I will sketch how better equidistribution estimates for primes in APs are linked to stronger bounds on the infimum limit of gaps between m consecutive primes. I will then show how a refinement of the q-van der Corput method can be used to improve on Polymath's equidistribution estimates and thus to obtain better bounds on short gaps between 3 or more primes.

Upcoming talks:

Katherine E. Stange, The local-global conjecture for Apollonian circle packings is false
(University of Colorado, Boulder) 

Thursday, January 23, 2025 (8am PST, 11am EST, 4pm GMT, 5pm CET, 6pm Israel Standard Time, 9:30pm Indian Standard Time)
Friday, January 24, 2025 (12am CST, 3am AEDT, 5am NZDT)

Abstract: Primitive integral Apollonian circle packings are fractal arrangements of tangent circles with integer curvatures.  The curvatures form an orbit of a 'thin group', a subgroup of an algebraic group having infinite index in its Zariski closure.  The curvatures that appear must fall into a restricted class of residues modulo 24. The twenty-year-old local-global conjecture states that every sufficiently large integer in one of these residue classes will appear as a curvature in the packing. We prove that this conjecture is false for many packings, by proving that certain quadratic and quartic families are missed. The new obstructions are a property of the thin Apollonian group (and not its Zariski closure), and are a result of quadratic and quartic reciprocity, reminiscent of a Brauer-Manin obstruction. Based on computational evidence, we formulate a new conjecture.  This is joint work with Summer Haag, Clyde Kertzer, and James Rickards.  Time permitting, I will discuss some new results, joint with Rickards, that extend these phenomena to certain settings in the study of continued fractions.


Hector Pasten, TBA
(Pontificia Universidad Católica de Chile)

Thursday, January 30, 2025 (8am PST, 11am EST, 4pm GMT, 5pm CET, 6pm Israel Standard Time, 9:30pm Indian Standard Time)
Friday, January 31, 2025 (12am CST, 3am AEDT, 5am NZDT)

Abstract: TBA


Alex Kontorovich, TBA
(Rutgers University

Thursday, February 6, 2025 (8am PST, 11am EST, 4pm GMT, 5pm CET, 6pm Israel Standard Time, 9:30pm Indian Standard Time)
Friday, February 7, 2025 (12am CST, 3am AEDT, 5am NZDT)

Abstract: TBA


Emmanuel Ullmo, TBA
(IHES

Thursday, February 13, 2025 (8am PST, 11am EST, 4pm GMT, 5pm CET, 6pm Israel Standard Time, 9:30pm Indian Standard Time)
Friday, February 14, 2025 (12am CST, 3am AEDT, 5am NZDT)

Abstract: TBA


Valérie Berthé, TBA
(IRIF, Université Paris Cité

Thursday, February 20, 2025 (8am PST, 11am EST, 4pm GMT, 5pm CET, 6pm Israel Standard Time, 9:30pm Indian Standard Time)
Friday, February 21, 2025 (12am CST, 3am AEDT, 5am NZDT)

Abstract: TBA


Shaoshi Chen, TBA
(Academy of Mathematics and Systems Science, Chinese Academy of Sciences

Thursday, February 27, 2025 (8am PST, 11am EST, 4pm GMT, 5pm CET, 6pm Israel Standard Time, 9:30pm Indian Standard Time)
Friday, February 28, 2025 (12am CST, 3am AEDT, 5am NZDT)

Abstract: TBA


Péter Varjú, TBA
(University of Cambridge

Thursday, March 6, 2025 (8am PST, 11am EST, 4pm GMT, 5pm CET, 6pm Israel Standard Time, 9:30pm Indian Standard Time)
Friday, March 7, 2025 (12am CST, 3am AEDT, 5am NZDT)

Abstract: TBA


Florian Karl Richter, TBA
(EPFL

Thursday, March 13, 2025 (9am PDT, 12pm EDT, 4pm GMT, 5pm CET, 6pm Israel Standard Time, 9:30pm Indian Standard Time)
Friday, March 14, 2025 (12am CST, 3am AEDT, 5am NZDT)

Abstract: TBA


Gergely Harcos, TBA
(Alfréd Rényi Institute of Mathematics

Thursday, March 20, 2025 (9am PDT, 12pm EDT, 4pm GMT, 5pm CET, 6pm Israel Standard Time, 9:30pm Indian Standard Time)
Friday, March 21, 2025 (12am CST, 3am AEDT, 5am NZDT)

Abstract: TBA


Andreas Strömbergsson, TBA
(Uppsala University

Thursday, March 27, 2025 (9am PDT, 12pm EDT, 4pm GMT, 5pm CET, 6pm Israel Standard Time, 9:30pm Indian Standard Time)

Friday, March 28, 2025 (12am CST, 3am AEDT, 5am NZDT)

Abstract: TBA


Stephanie Chan, TBA
(IST Austria)

Thursday, April 3, 2025 (8am PDT, 11am EDT, 4pm BST, 5pm CEST, 6pm IDT, 8:30pm IST, 11pm CST)
Friday, April 4, 2025 (2am AEDT, 4am NZDT)

Abstract: TBA


Mayank Pandey, TBA
(Princeton University)

Thursday, April 10, 2025 (8am PDT, 11am EDT, 4pm BST, 5pm CEST, 6pm IDT, 8:30pm IST, 11pm CST)
Friday, April 11, 2025 (1am AEST, 3am NZST)

Abstract: TBA


Dimitris Koukoulopoulos, TBA
(University of Montreal)

Thursday, April 17, 2025 (8am PDT, 11am EDT, 4pm BST, 5pm CEST, 6pm IDT, 8:30pm IST, 11pm CST)
Friday, April 18, 2025 (1am AEST, 3am NZST)

Abstract: TBA


Matthew de Courcy-Ireland, TBA
(Stockholm University)

Thursday, April 24, 2025 (8am PDT, 11am EDT, 4pm BST, 5pm CEST, 6pm IDT, 8:30pm IST, 11pm CST)
Friday, April 25, 2025 (1am AEST, 3am NZST)

Abstract: TBA


Vivian Kuperberg, TBA
(ETH Zürich)

Thursday, May 1, 2025 (8am PDT, 11am EDT, 4pm BST, 5pm CEST, 6pm IDT, 8:30pm IST, 11pm CST)
Friday, May 2, 2025 (1am AEST, 3am NZST)

Abstract: TBA


Martin Widmer, TBA
(Royal Holloway, University of London)

Thursday, May 8, 2025 (8am PDT, 11am EDT, 4pm BST, 5pm CEST, 6pm IDT, 8:30pm IST, 11pm CST)
Friday, May 9, 2025 (1am AEST, 3am NZST)

Abstract: TBA


Peter Koymans, TBA
(Utrecht University)

Thursday, May 15, 2025 (8am PDT, 11am EDT, 4pm BST, 5pm CEST, 6pm IDT, 8:30pm IST, 11pm CST)
Friday, May 16, 2025 (1am AEST, 3am NZST)

Abstract: TBA


Carlo Pagano, TBA
(Concordia University)

Thursday, May 22, 2025 (8am PDT, 11am EDT, 4pm BST, 5pm CEST, 6pm IDT, 8:30pm IST, 11pm CST)
Friday, May 23, 2025 (1am AEST, 3am NZST)

Abstract: TBA


Will Sawin, TBA
(Princeton University)

Thursday, June 5, 2025 (8am PDT, 11am EDT, 4pm BST, 5pm CEST, 6pm IDT, 8:30pm IST, 11pm CST)
Friday, June 6, 2025 (1am AEST, 3am NZST)

Abstract: TBA


Jan Hendrik Bruinier, TBA
(TU Darmstadt)

Thursday, June 26, 2025 (8am PDT, 11am EDT, 4pm BST, 5pm CEST, 6pm IDT, 8:30pm IST, 11pm CST)
Friday, June 27, 2025 (1am AEST, 3am NZST)

Abstract: TBA


Sponsors:

We gratefully acknowledge the generous support of: