We meet on Friday at 16:00 on Sugimoto Campus of Osaka Metropolitan University.

The venue is Room E408 in Science Building E. We also broadcast the seminar via Zoom.

Organizers: Yohsuke Matsuzawa, Ryo Kanda, Takamichi Sano, Hiroyuki Minamoto

Next Talk

Friday, January 9, 2026, 16:00-17:00
Venue: Room F415 in Science Building F

Toshitaka Aoki (Kobe University)
Title: On the preservation of interval resolutions of poset representations via contraction functors
Abstract: A persistence module (or representation) is a covariant functor from a given poset to the category of vector spaces. In standard persistent homology, one-parameter persistence modules play a fundamental role, since they are guaranteed to decompose into interval modules. In this talk, we first recall the basics of the representation theory of posets, introducing some invariants motivated by multiparameter persistent homology analysis. The class of interval modules is of particular importance. Note that our posets are not necessarily finite. We then introduce a functor, called the contraction functor, defined as the left Kan extension of the induction functor with respect to a certain full subposet embedding. In this setting, both the induction and contraction functors preserve the interval-decomposability of modules. Using this adjunction, we prove that the induction functor preserves interval resolutions of modules. As an application, we show that the interval resolution global dimension does not change when inserting an $A_n$-type chain of arbitrary length. This talk is based on a joint work with Shunsuke Tada (arXiv:2506.21227).

Schedule

Monday, January 26, 2026, 16:00-17:00
Venue: Room F415 in Science Building F

Yasuaki Ogawa (Kansai University)
Title: TBA
Abstract: TBA

Support (FY 2025)

Sugimoto Algebra Seminars are supported by:

• JSPS KAKENHI Grant Number JP24K06693

• Osaka Central Advanced Mathematical Institute (MEXT Promotion of Distinctive Joint Research Center Program JPMXP0723833165), Osaka Metropolitan University