Category theory. More specifically, I am interested in the following topics.

• formal category theory.

• (virtual) double categories.

• other higher categories.

  • weak ω-category à la Batanin and Leinster.

  • triple categories.

  • multiple categories.

On the other hand, I am also interested in computer science, including

• realizability.

• homotopy type theory.

Soichiro Fujii, H., Yuki Maehara, Weakly Invertible cells in a weak ω-category  arXiv:2303.14907

H., Hayato Nasu, Double categories of relations relative to factorisation systems  arXiv:2310.19428

Soichiro Fujii, H., Yuki Maehara, ω-weak equivalences between weak ω-categories arXiv:2406.13240

CSCAT2025, Bivirtual double categories and localisation of composing cells. Sojo university. 10th Mar 2025. slides

Computer Science Theory Seminar, Factorisation systems and (virtual) equipments. Logic and Semantics group in TTÜ, Tallinn. 12th Dec 2024. slides

Second Virtual Workshop on Double Categoires, Double categories of relations relative to factorisation systems. Online. 30th Oct 2024

AustMS 2023, Double categories of relations relative to factorisation systems. University of Queensland. 6th Dec 2023

Australian Category Seminar, Factorisation systems and equipments. Macquarie University. 29th Nov 2023

Kengo Hirata

Yuto Kawase

Hayato Nasu

Ryuya Hora

Yuki Maehara

Soichiro Fujii

Takahiro Sanada