My work lies at the interface of mathematics and computer science. I study the computational complexity of constraint satisfaction problems and their approximation and promise variants using universal algebra, homotopy theory, category theory, and logic.
I was a post-doc at ISTA (2022–23), Oxford (2021–22), Durham University (2018–21), TU Dresden (2016–18), and Jagiellonian University (2016). I received my PhD at Charles University in Prague on 29 Feb 2016. My advisor was Libor Barto.
upcoming travels
- Symmetry in Efficient Computation with Local Constraints
- Simons Institute, Berkeley, US, March–April 2027
selected papers
Meyer, S., & Opršal, J. (2025).
A topological proof of the Hell–Nešetřil dichotomy
SODA 2025, pp. 4507–4519.
doi:10.1137/1.9781611978322.154, arXiv:2409.12627v2.
Dalmau, V., & Opršal, J. (2024).
Local consistency as a reduction between constraint satisfaction problems
LICS 2024, 29:1–15.
doi:10.1145/3661814.3662068, arXiv:2301.05084v3.
Krokhin, A., Opršal, J., Wrochna, M., & Živný, S. (2023).
Topology and adjunction in promise constraint satisfaction.
SIAM Journal on Computing, 52(1), 38–79.
doi:10.1137/20M1378223, arXiv:2003.11351.
Barto, L., Bulín, J., Krokhin, A., & Opršal, J. (2021).
Algebraic approach to promise constraint satisfaction.
J. ACM, 68(4), 28:1–66.