About me
I am a PhD student in mathematics at the École Polytechnique Fédérale de Lausanne (EPFL), under the supervision of Kathryn Hess. My thesis is on the theoretical foundations of topological data analysis (TDA). More broadly, I am interested in algebra, topology and category theory, and their applications in data science and computational fields.
Contact
Bjørnar Gullikstad Hem
École Polytechnique Fédérale de Lausanne
Office: MA B3 485
Email: bjornar.hem (at) epfl.ch
Research
Publications:- The discrete flow category: structure and computation, Journal of Applied and Computational Topology 8, 2401–2450 (2024). Available here
- Decomposing multipersistence modules using functor calculus (2025). Preprint available at arXiv:2510.06178
- Poset functor cocalculus and applications to topological data analysis (2025). Preprint available at arXiv:2501.05996
Talks
- (Upcoming) February 2026: TBD, Topological Data Analysis and Representation Theory 2026, Tohoku Univeristy.
- (Upcoming) 22. December 2025: TBD, Bilkent university topology seminar (online talk).
- October 2025: Functor calculus and multiparameter persistence, the 5th Workshop on Computational Topology, the State University of New York at Albany.
- December 2024: Functor calculus for multi-persistent homology, the University of Calgary's seminar on logic, mathematics, and computer science (online talk).
- August 2024: An analogue of manifold calculus for multi-persistence modules, the Young Topologists Meeting 2024, University of Münster.
- April 2024: An analogue of manifold calculus for multi-persistence modules, the International workshop on AI and Topology, University of Copenhagen.
