Jaco Ruit

I am a postdoctoral fellow at the Hong Kong University of Science and Technology in the group of Quoc Ho. Before that, I was a postdoc at the Max Planck Institute for Mathematics with Viktoriya Ozornova, and a Ph.D. candidate at Utrecht University with Lennart Meier. My research interests lie in the realm of homotopy theory, with a main focus on higher category theory.

Publications

• Formal category theory in ∞-equipments I
  To appear in Algebraic & Geometric Topology.
  arXiv:2308.03583
• A short proof of the straightening theorem
  with F. Hebestreit and G. Heuts
  Transactions of the American Mathematical Society B, 12 (2025), 697–747.
  arXiv:2111.00069
• A pasting theorem for iterated Segal spaces
  Journal of Pure and Applied Algebra, 228 (2024), no. 11, 107712.
  arXiv:2210.04549

Preprints

• Day convolution for algebraic patterns
  with T. Blom and F. Loubaton
  Submitted. Last updated on: 31 Mar. 2026.
  arXiv:2603.29815
• On the squares functor and the Gaitsgory–Rozenblyum conjectures
  with F. Loubaton
  Submitted. Last updated on: 25 Jul. 2025.
  arXiv:2507.07807
• Homotopy coherent companionships and conjunctions
  Submitted. Last updated on: 8 Apr. 2025.
  arXiv:2408.14335
• Formal category theory in ∞-equipments II
  Last updated on: 8 Aug. 2024.
  arXiv:2408.1519

Theses

• On multiple ∞-categories and formal category theory via ∞-equipments
  Ph.D. thesis, Utrecht University, Apr. 2025.
• Grothendieck constructions in higher category theory
  Master's thesis, Utrecht University, Aug. 2020.