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The seminar meets on one Friday every month with two talks, at 2:30-3:30 pm Paris time and 4-5 pm Paris time. There will be online coffee breaks between the two talks. For time conversion and Zoom link please visit our researchseminars page.

Date Speakers Titles and Abstracts
December 11th, 2020
2:30-3:30 pm CET

4:00-5:00 pm CET

Jean-Louis Colliot-Thélène
CNRS and Paris-Saclay University (Orsay)

Jordan Ellenberg
UW Madison

Jumps in the rank of the Mordell-Weil group / Sauts du rang du groupe de Mordell-Weil
Slides (in French) and recording of the talk

Some questions around counting rational points on stacks
Slides and recording of the talk
January 15th, 2021
2:30-3:30 pm CET

4:00-5:00 pm CET

Stephanie Chan
University of Michigan

Carlo Pagano
University of Glasgow and Max Planck Institute for Mathematics (Bonn)

A density of ramified primes
Slides and recording of the talk

On the statistics of number fields, integral points and Arakelov ray class groups
Recording of the talk
February 19th, 2021
2:30-3:30 pm CET

4:00-5:00 pm CET

Ratko Darda
Paris University (Paris 7)

Rosa Winter
Max Planck Institute for Mathematics in the Sciences (Leipzig)

Manin conjecture for algebraic stacks
Slides and recording of the talk

Density of rational points on a family of del Pezzo surfaces of degree 1
Slides and recording of the talk
March 19th, 2021
2:30-3:30 pm CET

4:00-5:00 pm CET

Damaris Schindler
Göttingen University

Arda Huseyin Demirhan
University of Illinois at Chicago

Campana points on toric varieties

Distribution of Rational Points on Toric Varieties: A Multi-Height Approach
Slides and recording of the talk
April 23rd, 2021
2:30-3:30 pm CEST

4:00-5:00 pm CEST

Shuntaro Yamagishi
Utrecht University

Miriam Kaesberg
Göttingen University

Density of rational points near/on compact manifolds with certain curvature conditions

On Artin’s Conjecture: Pairs of Additive Forms
Slides and recording of the talk
May 14th, 2021
11:00-11:30 am CEST

12:00-12:30 pm CEST

2:30-3:30 pm CEST

4:00-4:30 pm CEST

Margherita Pagano
Leiden University

Alexandre Lartaux

Samir Siksek
Warwick University

Alec Shute
IST Austria
An example of Brauer-Manin obstruction to weak approximation at a prime with good reduction
Slides and recording of the talk

On the number of ideals with norm a binary form of degree 3
Slides and recording of the talk

Integral points on punctured curves and punctured abelian varieties
Slides and recording of the talk

Sums of four squareful numbers
Slides and recording of the talk
June 4th, 2021
10:00-11:00 am CEST

5:30-6:20 pm CEST

Sho Tanimoto
Nagoya University

Rena Chu
Duke University
Rational curves on del Pezzo surfaces in positive characteristic
Slides and recording of the talk

Constant root number on integer fibres of elliptic surfaces
Slides and recording of the talk

Mailing list

If you want to receive the links to the talks and coffee breaks, there are two ways. You can fill out this form. Or (maybe easier) send a blank email to and click the link in the email we send in reply. If you can’t send a blank email you can put any gibberish in there. If you can’t find our emails please check your spam folder. You can also see the Zoom links on our researchseminars page.

Coffee breaks and house rules

We kindly ask that you use your full name in the Zoom session and coffee meeting. While attending the coffee break, please either leave the Zoom meeting or route the Zoom audio to a pair of headphones.

A link for the coffee breaks will be posted in the Zoom meeting and sent to the mailing list.

To join the coffee break you will need to use Firefox or Chrome to open the link. (Except on iPad/iPhone, where you must use Safari.)

If you have trouble, try both Chrome and Firefox, or do a Google search for Chrome microphone permissions / Firefox microphone permissions.

Friends of ZORP

You might also be interested in these seminars:

Date Event name More information
May 10-14 and May 17-21, 2021 Hausdorff School : “The circle method” For all the information, registration and Zoom link, see here
April 30th, 2021
15:00-16:00pm BST (16:00-17:00 CEST)
Manchester Pure Maths Colloquium Ken Ono, University of Virginia - Can’t you just feel the moonshine?
Contact Vandita Patel for Zoom link
Video recording online
(November 20th, 2020)
Yuri Manin, “Homotopy spectra and Diophantine equations” A Harvard Math Science Literature Lecture.
Lecture series webpage; watch the talk
One Friday each month Séminaire “Variétés Rationelles” Seminar webpage with mailing list information etc.
One every three months WORKing seminar on Diophantine geometry Seminar webpage with all the information.


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