熊本大学　大学院先端科学研究部　

作用素環論や作用素環に関連するホモトピー群を研究しています.

メイルアドレス　staro[@]educ.kumamoto-u.ac.jp   [@]を＠にお願いします.

Papers and preprints

1.  The homotopy groups of the automorphism groups of Cuntz-Toeplitz algebras,  J. Math. Soc. Japan, (2020) . arXiv:1903.02796 

2.  The group structure of the homotopy set whose target is the automorphism group of the Cuntz algebra,  (Joint Work with Prof.  Masaki Izumi),  International Journal of Mathematics, Vol. 30, No. 11, (2019) .  arXiv:1903.04809 

3.  A topological invariant for continuous fields of Cuntz algebras.  arXiv:2002.06807  Math. Annalen. (2020) 

4.  A topological invariant for continuous fields of Cuntz algebras II.  arXiv:2010.00758 Proc. Amer. Math. Soc. 150(2022), 1059-1070 

5. The Reciprocal Kirchberg Algebras.  arXiv:2204.11199  Journal of Functional Analysis. (2024) , https://doi.org/10.1016/j.jfa.2024.110395 

6. Spanier-Whitehead  K-duality and Duality of Extensions of C*-algebras. (Joint Work with Prof. Ulrich Pennig )International Mathematics Research Notices, rnae242, https://doi.org/10.1093/imrn/rnae242  arXiv:2403.20081 

7. On the homotopy groups of the automorphism groups of Cuntz-Krieger algebras, (Joint Work with Prof. Kengo Matsumoto) arXiv:2404.06115 Journal of Noncommutative Geometry. 

8. Total extension groups for unital Kirchberg algebras, (Joint Work with Prof. Kengo Matsumoto), arXiv:2408.09359  to appear in Math. Scand.

9. Reciprocal Cuntz--Krieger Algebras, (Joint Work with Prof. Kengo Matsumoto), arXiv:2502.18126 

10. Topological full groups arising from Cuntz and Cuntz-Toeplitz algebras and their crossed products, (Joint Work with Dr. Ryoya Arimoto ),  arXiv:2504.05145  (If you can not see the PDF please try HTML and SOURCE FILES)

11. Ergodic automorphisms on Kirchberg Algebras, (Joint Work with Prof. Kengo Matsumoto), arXiv:2505.06115 

Talks

・The homotopy groups of the automorphism groups of Cuntz-Toeplitz algebras,  Kyoto Operator Algebra Seminar @ 京都,  January 2019

・Cuntz-Toeplitz環の自己同型群のホモトピー群, 日本数学会@金沢, September 2019

・The homotopy groups of the automorphism groups of Cuntz-Toeplitz algebras,  作用素環の最近の進展　RIMS @ 京都, September 2019

・Cuntz-Toeplitz環の自己同型群のホモトピー群について,  名大多元数理量子解析セミナー@名古屋, October 2019

・The homotopy groups of the automorphism groups of Cuntz-Toeplitz algebras, 東大作用素環セミナー@東京,  November 2019

・A topological invariant for continuous fields of Cuntz algebras,  作用素環の最近の進展　RIMS@京都,  January 2020

・A topological invariant for continuous fields of  Cuntz algebras, GAPT Seminar@Cardiff, March 2020

・Cuntz環のバンドルの不変量について, 作用素論作用素環論研究集会 (Zoom),  November 2020

・Cuntz環のバンドルの不変量について, RIMS　作用素環と量子力学系 (Zoom), February 2021

・Bundles of the Cuntz algebras, RIMS　作用素環論の最近の進展(Zoom), Sep. 2021

・Kirchberg algebras sharing the same homotopy groups of their automorphism groups, 解析、幾何合同セミナー@千葉大学,  May 2022

・Kirchberg algebras sharing the same homotopy groups of their automorphism groups, 東大作用素環セミナー@東京,  June 2022

・Dadarlat--Pennig理論について, 関数解析研究会@京都, August 2022

・The Reciprocal Kirchberg Algebras, 名大量子解析セミナー@名古屋, October 2022

・The Reciprocal Kirchberg Algebras, GAPT seminar@Cardiff,  December 2022

・The Reciprocal Kirchberg Algebras, KOAS@Kyoto, January 2023

・The bundles of C*-algebras and the duality for KK-theory, KOAS@Kyoto, April 2023

・The Reciprocal Kirchberg algebras, OAS Workshop in Issac Newton Institute@Cambridge, July 2023 

・The Spanier--Whitehead duality for KK-groups and its applications,  RIMS　作用素環論の最近の進展@京都,  January 2024

・Spanier--Whitehead duality and its application  to a duality of extensions of C*-algebras,  GAPT Seminar@Cardiff, February 2024

・A duality for KK-theory and extensions  of C*-algebras,  名大量子解析セミナー@名古屋, Mar. 2024

・A duality of KK-theory and its application to the extensions of C*-algebras,  日本数学会@大阪, Mar. 2024

・Cuntz--Krieger環の自己同型群のホモトピー群の計算について, 作用素環, エルゴード理論セミナー@九州, June. 2024

・The ext groups and homotopy groups of the automorphism groups of Cuntz-Krieger algebras, 東大作用素環セミナー@東京, June. 2024

・The ext groups and homotopy groups of the automorphism groups of Cuntz-Krieger algebras, KOAS@京都, June. 2024

・The bundles of C*-algebras,  Operator Algebras in the South of UK @Southampton, Sep. 2024

・Some groups to classify unital Kirchberg algebras, RIMS 作用素環の最近の進展＠京都, Sep. 2024

・Torus actions on the Cuntz algebras,  bundles, and their reciprocal algebras, GAPT Seminar@Cardiff, Jan. 2025

・Cuntz--Krieger algebras their Toeplitz extensions and reciprocal algebras, @Newcastle, Feb. 2025 

・The Reciprocal Cuntz-Krieger algebras, 日本数学会@東京, March. 2025

・作用素環の人に向けたホモトピー論入門, 関数解析研究会@愛媛, Sep. 2025

・Ergodic automorphisms on unital Kirchberg algebras, 日本数学会＠名古屋, 2025