L-functions and Motives in Niseko 2024
September 15-20, 2024
About This Conference
The objective of this conference is to promote communications between mathematicians working on subjects related to L-functions and Motives. The venue is in the middle of national parks in Hokkaido and conveniently accessible from Sapporo city or New Chitose Airport. This is a continuation of the conferences held in 2015, 2017, 2019 and 2022.
Speakers
Toshiro Hiranouchi (Kyushu Institute of Technology)
Tetsushi Ito (Kyoto University)
Ryomei Iwasa (Université Paris-Saclay)
Wataru Kai (Tohoku University)
Tomokazu Kashio (Tokyo University of Science)
Junnosuke Koizumi (RIKEN)
Teruhisa Koshikawa (RIMS)
Yoshinori Mishiba (Tohoku University)
Kazuaki Miyatani (Tokushima University)
Yoshiyasu Ozeki (Kanagawa University)
Atsuhira Nagano (Kanazawa University)
Akio Nakagawa (Kanazawa University)
Kazuma Shimomoto (Tokyo Institute of Technology)
Daichi Takeuchi (RIKEN)
Titles and Abstracts
Toshiro Hiranouchi , Extended differential symbol and the Weil reciprocity law with modulus
TBA
Tetsushi Ito, TBA
TBA
Ryomei Iwasa, Atiyah duality for motivic spectra
TBA
Wataru Kai, Linear patterns of prime elements in number fields
I will discuss my recent result that gives a sufficient condition for a set of finitely many polynomials of degree 1 with coefficients in a number ring to attain simultaneous prime values. This extends a 2012 theorem of Green-Tao-Ziegler from the case of Z to the general case. Time permitting, I will mention how this can be applied to produce (modestly) new families of varieties over number fields which satisfy the Hasse principle for rational points by using the so-called fibration method.
Tomokazu Kashio, On periods and the absolute Frobenius on Fermat curves
TBA
Junnosuke Koizumi, TBA
TBA
Teruhisa Koshikawa, Cohomology of log prismatic F-crystals
TBA
Yoshinori Mishiba, On algebraic relations among values of multiple polylogarithms in positive characteristic
TBA
Kazuaki Miyatani, TBA
TBA
Atsuhira Nagano, Kummer-like surfaces and their partner surfaces
Kummer surfaces for principally polarized Abelian surfaces are K3 surfaces defined by quartic equations. They are important in algebraic geometry and number theory. Particular families of lattice polarized K3 surfaces naturally contain the family of Kummer surfaces. The speaker is expecting that such families, which he calls the families of Kummer-like surfaces, are also interesting objects of research. In this talk, we will see properties of Kummer-like surfaces, such as lattices, periods, elliptic fibrations or defining equations. In order to study them, the speaker will introduce useful K3 surfaces, which he calls partner surfaces. Moreover, if there is enough time, the speaker will show the relation among K3 surfaces studied by Matsumoto-Sasaki-Yoshida (1992), Clingher-Doran (2012), Clingher-Malmendier-Shask (2019), N. (2021) and N.-Shiga (2023).
Akio Nakagawa, Geometric interpretation of certain transformation formulas for hypergeometric functions over finite fields
TBA
Yoshiyasu Ozeki, Some Kummer extensions over maximal cyclotomic fields, a finiteness theorem of Ribet and TKND-AVKF fields
It is a theorem of Ribet that an abelian variety defined over a number field K has only finitely many torsion points with values in the maximal cyclotomic extension field K^cyc of K. Recently, Rössler and Szamuely generalized Ribet's theorem in terms of the étale cohomology with Q/Z-coefficients of a smooth proper variety. In this talk, I will explain that the same finiteness holds even after replacing K^cyc with the field obtained by adjoining to K all roots of all elements of a certain subset of K. Furthermore, I give some new examples of TKND-AVKF fields; the notion of TKND-AVKF is introduced by Hoshi, Mochizuki and Tsujimura, and TKND-AVKF fields are expected as one of suitable base fields for anabelian geometry. This is a joint work with Takahiro Murotani.
Kazuma Shimomoto, Perfectoid towers, Frobenius lifts and lim Cohen-Macaulay sequences
I will talk about several ways of constructing non-regular Noetherian rings of mixed characteristic with Frobenius lifts. The resulting rings have some interesting singularities that were not known previously. Then I will talk about their connections with perfectoid towers and potential applications to an open problem in commutative algebra. This is a report on a joint work with S. Ishiro. R. Ishizuka and K. Nakazato.
Daichi Takeuchi, Constructing a nearby cycles functor for functions on mixed characteristic schemes
TBA
Program
Venues : Niseko Residents Center (main sessions), Setsu Niseko (poster sessions)
Sunday 15
Arrival
Monday 16
9:30-11:00 : Poster Session / Free Discussion
13:20-14:20 : Toshiro Hiranouchi, Extended differential symbol and the Weil reciprocity law with modulus
14:35-15:35 : Ryomei Iwasa, Atiyah duality for motivic spectra
15:50-16:50 : Junnosuke Koizumi, TBA
17:05-18:05 : Daichi Takeuchi, Constructing a nearby cycles functor for functions on mixed characteristic schemes
Tuesday 17
9:30-11:00 : Poster Session / Free Discussion
13:20-14:20 : Yoshiyasu Ozeki, Some Kummer extensions over maximal cyclotomic fields, a finiteness theorem of Ribet and TKND-AVKF fields
14:35-15:35 : Wataru Kai, Linear patterns of prime elements in number fields
15:50-16:50 : Akio Nakagawa, Geometric interpretation of certain transformation formulas for hypergeometric functions over finite fields
17:05-18:05 : Yoshinori Mishiba, On algebraic relations among values of multiple polylogarithms in positive characteristic
19:00- : Banquet
Wednesday 18
9:30-10:30 : Kazuma Shimomoto, Perfectoid towers, Frobenius lifts and lim Cohen-Macaulay sequences
10:50-11:50 : Teruhisa Koshikawa, Cohomology of log prismatic F-crystals
Afternoon : Excursion
Thursday 19
9:30-11:00 : Poster Session / Free Discussion
13:20-14:20 : Tomokazu Kashio, On periods and the absolute Frobenius on Fermat curves
14:35-15:35 : Kazuaki Miyatani, TBA
15:50-16:50 : Atsuhira Nagano, Kummer-like surfaces and their partner surfaces
17:05-18:05 : Tetsushi Ito, TBA
Friday 20
Departure
Excursion
We will organize a hiking on Wednesday afternoon (subject to weather conditions).
Accommodation
Fee (per night, breakfast and tax included) : Two Bedroom Suite for 4 persons (with 2 twin bed rooms) - ¥12,600 (per pers.). Single use of one of the twin bedrooms is possible (for a limited number of rooms) with additional fee ¥7,000.
We will organize a banquet on Tuesday evening at méli mélo - Yuki No Koe - : ¥7,000 (food and 2 drinks).
Lunch and dinner :
There are many restaurants around and inside the hotel.
Each suite is equipped with a complete kitchen.
Wifi connection is available at Setsu Niseko and Niseko Residents Center.
The hotel has a children's room and can arrange a qualified childcare worker or a babysitter.
How to get there
We will book the following buses. The fare will be approximately ¥4,000 (one way).
Sep. 15, 15:00 New Chitose Airport - 17:30 Setsu Niseko.
Sep. 20, 9:30 Setsu Niseko - 12:00 New Chitose Airport.
You can also take a train from New Chitose Airport (via Sapporo and Otaru) to Kutchan or Niseko, and take a shuttle bus to the hotel. Google trains
Registration
Deadline : August 15, 2024.
Poster Session : Please give a (tentative) title if you offer a presentation at the poster session.
Financial Support : We offer financial support for limited participants, mainly speakers and young participants.
Participants will be limited to 50 people on a first-come, first-served basis.
A confirmation email will be sent to the registered email address.
You can alter your registration using the link in the confirmation email.
Acknowledgments
This conference is supported by the JSPS Kakenhi Grant : 19K03391 (M. Asakura), 20K03566 (K. Sato), 24K06682 (N. Otsubo).
Address
Setsu Niseko : 1-2-6-9, Niseko Hirafu, Kutchan, 044-0080 Japan
Niseko Residents Center : Fujimi 95, Niseko, 048-1501 Japan