3 papers
cs.DS2026
Approximating spin systems on planar graphs
Heng Guo, Xinyuan Zhang
We show that the hard-core partition function admits a fully polynomial-time randomised approximation scheme (FPRAS) on planar graphs when the activity is a sufficiently small cons…
cs.DS2026
Fast counting and sampling for ferromagnetic two-spin systems
Weiming Feng, Heng Guo, Yichun Yang
We introduce two new models equivalent to ferromagnetic two-spin systems: a weighted subgraph model and a random cluster type model. Using these new connections, we obtain an effic…
cs.DS2024
Deterministic counting from coupling independence
Xiaoyu Chen, Weiming Feng, Heng Guo +2
We show that spin systems with bounded degrees and coupling independence admit fully polynomial time approximation schemes (FPTAS). We design a new recursive deterministic counting…