Research
My research is in combinatorics, with connections to complex dynamics,
statistical physics, and theoretical computer science.
I study zeros of graph polynomials, computational complexity
of partition functions, and, more recently,
the Shannon capacity of graphs and reconfiguration problems.
I was a postdoctoral researcher at the
Korteweg-de Vries Institute for Mathematics
at the University of Amsterdam, working with
Ross Kang (2022–2026).
I obtained my PhD there in 2022,
supervised by
Guus Regts and Han Peters.
Publications
A group-theoretic approach to Shannon capacity of graphs and a limit theorem from lattice packings
Pjotr Buys, Sven Polak, Jeroen Zuiddam, 2025.
A shorter version appeared in EuroComb 2025.
Triangle-free graphs with the fewest independent sets
Pjotr Buys, Jan van den Heuvel, Ross J. Kang, 2025.
Reconfiguration of Independent Transversals
Pjotr Buys, Ross J. Kang, Kenta Ozeki.
Random Structures & Algorithms, 67(1), e70025, 2025.
The asymptotic spectrum distance, graph limits, and the Shannon capacity
David de Boer, Pjotr Buys, Jeroen Zuiddam, 2024.
A shorter version appeared in EuroComb 2025.
On boundedness of zeros of the independence polynomial of tori
David de Boer, Pjotr Buys, Han Peters, Guus Regts.
In Algebraic, Complex, and Arithmetic Dynamics, Simons Symposia, Springer, 2026. To appear.
Optimal Zero-Free Regions for the Independence Polynomial of Bounded Degree Hypergraphs
Ferenc Bencs, Pjotr Buys
Random Structures & Algorithms, 66(4), e70018, 2025.
The Limit of the Zero Locus of the Independence Polynomial for Bounded Degree Graphs
Ferenc Bencs, Pjotr Buys, Han Peters
Michigan Mathematical Journal, 75(2), 423–448, 2025.
Uniqueness of the Gibbs measure for the anti-ferromagnetic Potts model on the infinite Δ-regular tree for large Δ
Ferenc Bencs, David de Boer, Pjotr Buys, Guus Regts
Journal of Statistical Physics, 190(8), Paper No. 140, 2023.
Zeros, chaotic ratios and the computational complexity of approximating the independence polynomial
David de Boer, Pjotr Buys, Lorenzo Guerini, Han Peters, Guus Regts
Mathematical Proceedings of the Cambridge Philosophical Society, 1–36, 2023.
Uniqueness of the Gibbs measure for the 4-state anti-ferromagnetic Potts model on the regular tree
David de Boer, Pjotr Buys, Guus Regts
Combinatorics, Probability and Computing, 32(1), 158–182, 2023.
Lee–Yang zeros and the complexity of the ferromagnetic Ising model on bounded-degree graphs
Pjotr Buys, Andreas Galanis, Viresh Patel, Guus Regts
Forum of Mathematics, Sigma, 10, e7, 2022.
Lee-Yang zeros of the antiferromagnetic Ising model
Ferenc Bencs, Pjotr Buys, Lorenzo Guerini, Han Peters
Ergodic Theory and Dynamical Systems, 1–35, 2021.
Cayley trees do not determine the maximal zero-free locus of the independence polynomial
Pjotr Buys
Michigan Mathematical Journal, 70(3), 635–648, 2021.
Talks
The Shannon capacity and the asymptotic spectrum distance
SPOR Seminar, TU Eindhoven
November 2025
slides
A limit theorem for Shannon capacity from lattice packings
EuroComb 2025
August 2025
slides
The number of independent sets in triangle-free graphs
Dutch Days of Combinatorics
March 2025
slides
Reconfiguration of Independent Transversals
Sum(m)it 280
July 2024
slides
Using complex dynamics to study graph partition functions
Quasiworld Seminar
December 2023
slides
Continuity of the Shannon capacity on graphs
Dutch Days of Combinatorics
March 2023
slides
The Zero-Locus and the Chaotic Behaviour of the Set of Two-Terminal Reliability Polynomials
Atlantic Graph Theory Seminar
March 2022
slides
Lee-Yang zeros and the complexity of the ferromagnetic Ising Model on bounded-degree graphs
Interplay between statistical mechanics, graph theory, computational complexity and holomorphic dynamics
June 2021
slides
Complex Dynamics and Graph Theory
ACM-SIAM Symposium on Discrete Algorithms (SODA21)
January 2021