3 papers
math.CO2026
Antiferromagnetic models are clique-minimizing
Joonkyung Lee, Jaehyeon Seo
An edge-weighted graph , possibly with loops, is antiferromagnetic if its adjacency matrix is entrywise nonnegative and has at most one positive eigenvalue, counted with multipl…
math.CO2026
Lower bounds for multivariate independence polynomials and their generalisations
Joonkyung Lee, Jaehyeon Seo
In statistical physics, the multivariate hard-core model describes a system of particles, each of which receives its own fugacity. In graph-theoretic language, the partition functi…
math.CO2025
Counting homomorphisms in antiferromagnetic graphs via Lorentzian polynomials
Joonkyung Lee, Jaeseong Oh, Jaehyeon Seo
An edge-weighted graph , possibly with loops, is said to be antiferromagnetic if it has nonnegative weights and at most one positive eigenvalue, counting multiplicities. The num…