Education
Department of Mathematics, School of Education, Waseda University（April 2010--March 2014）
Mathematics Education major, Graduate School of Education, Waseda University（April 2014--March 2016）
Master of Science, Waseda University（March 25th, 2016）
Master Thesis：On the realizability of non-simple hyperbolic Coxeter hexahedra（in Japanese）
Supervisor：Prof. Yohei KomoriCurriculum Area Sciences major, Graduate School of Education, Waseda University（April 2016--March 2019）
Doctor of Science, Waseda University（March 15th, 2019）
Thesis：Arithmetic properties of growth rates of hyperbolic Coxeter groups
Supervisors：Prof. Yohei Komori and Prof. Ruth Kellerhals
Academic Positions
JSPS Research Fellowship for Young Scientists DC2（April 2017--March 2019）
Assistant Professor, Waseda University（April 2019--March 2023）
Part-time Lecturer, Josai University (Complex analysis, Discrete mathematics)（April 2020--present）
Part-time Lecturer, Tokyo City University (Linear algebra)（September 2020--March 2021）
Senior Lecturer, Liberal Arts Education Center, Ashikaga University (April 2023--present)
Grants
KAKENHI Grant-in-Aid for JSPS Fellows
Research Subject Name：Realizability of hyperbolic Coxeter polytopes and their growth rates
Project Period：April 2017-- March 2021KAKENHI Grant-in-Aid for Early-Career Scientists
Research Subject Name：Study of the continuity of growth rates and spectral radii on the space of marked groups
Project Period：April 2020-- March2024
Awards
Azusa Ono Memorial Awards of Waseda University（March 2018）
Title of the paper：Growth rates of 3-dimensional hyperbolic Coxeter groups are Perron numbers (arXiv pdf)
Research Visits
Research Visitor at University of Fribourg, hosted by Ruth Kellerhals
period：August 2 and September 11, 2016
August 8 and September 16, 2017
July 13 and September 15, 2018)
February 18 and March 9, 2019)
June 13 and July 6, 2019)
August 8 and September 14, 2022Participant of the conference ``Growth in Topology and Number Theory: Volumes, Entropy and L2-torsion"
period：July 9 to 13, 2018Research Visitor at University of Bologna, hosted by Stefano Riolo
period：August 31 and September 2, 2022Participant of the conference ``Groups of Dynamical Origins, Automata and Spectra"
period：March 19 and March 24, 2023
Research Interests
Hyperbolic Geometry：Deformation theory and rigidity of discrete reflection groups and hyperbolic polytopes
Geometric Group Theory：Topological properties of the set of Coxeter groups in the space of marked groups and the continuity of the quantities related to Coxeter groups
Contact and Address
e-mail：yshigetomo@suou.waseda.jp
Address：268-1,Omaecho,Ashikaga,Tochigi, 326-8558, Japan