• Search Research Projects
  • Search Researchers
  • How to Use
  1. Back to project page

2021 Fiscal Year Annual Research Report

K-theoretic enumerative invariants and q-difference equations

Research Project

Project/Area Number 19F19802
Research InstitutionThe University of Tokyo

Principal Investigator

MILANOV Todor  東京大学, カブリ数物連携宇宙研究機構, 教授 (80596841)

Co-Investigator(Kenkyū-buntansha) ROQUEFEUIL ALEXIS  東京大学, カブリ数物連携宇宙研究機構, 外国人特別研究員
Project Period (FY) 2019-11-08 – 2022-03-31
Keywordsquantum K-theory / q-difference equations
Outline of Annual Research Achievements

We got two interesting results. The first one is related to the problem of confluence in the theory of q-difference equations. Namely, we proved that the small K-theoretic J-functions of a smooth projectve variety with non-negative first Chern class has a limit as q->1 and this limit coincides with the small cohomological J-function. Here, non-negative first Chern class means that the natural pairing of the 1st Chern class of the tangent bundle and the homology class of an irreducible curve is a non-negative number. The limit is taken after rescaling each Novikov variable in the K-theoretic J-function by an appropriate power of q-1.Moreover, we expect that our argument can be generalized so one can prove the confluence of the big J-function and the confluence of the quantum q-difference equations. It is also expected that the positivity condition of the 1st Chern class is redundant but removing this condition seems to be a challenging problem. Our second result is in the settings of toric geometry. We were able to identify explicitly the small J-function of a Fano toric manifold of Picard rank 2 with a certain q-oscillatory integral. The latter was introduced by Givental in order to provide a solution of the quantum q-difference equations and it can be viewed as a first step towards constructing or fomrulating mirror symmetry in quantum K-theory.

Research Progress Status

令和3年度が最終年度であるため、記入しない。

Strategy for Future Research Activity

令和3年度が最終年度であるため、記入しない。

  • Research Products

    (4 results)

All 2022 2021

All Presentation (4 results) (of which Int'l Joint Research: 1 results,  Invited: 4 results)

  • [Presentation] q-oscillatory integrals in quantum K-theory2022

    • Author(s)
      Alexis Roquefeuil
    • Organizer
      Universite d'Angers
    • Int'l Joint Research / Invited
  • [Presentation] Confluence for the K-theoretic J-function2021

    • Author(s)
      Todor Milanov
    • Organizer
      Riken iTHEMS Math Seminar
    • Invited
  • [Presentation] K-theoretic Gromov--Witten invariants and q-difference equations2021

    • Author(s)
      Alexis Roquefeuil
    • Organizer
      Rikkyo Mathematical Physics seminar
    • Invited
  • [Presentation] q-oscillatory integrals and confluence in quantum K-theory2021

    • Author(s)
      Alexis Roquefeuil
    • Organizer
      Waseda University, Special geometry, mirror symmetry, and integrable systems
    • Invited

URL: 

Published: 2022-12-28  

Information User Guide FAQ News Terms of Use Attribution of KAKENHI

Powered by NII kakenhi