3 papers
cs.CC2025
Safety Analysis in the NGAC Model
Brian Tan, Ewan S. D. Davies, Indrakshi Ray +1
We study the safety problem for the next-generation access control (NGAC) model. We show that under mild assumptions it is coNP-complete, and under further realistic assumptions we…
math.CO2025
On expectations and variances in the hard-core model on bounded degree graphs
Ewan Davies, Juspreet Singh Sandhu, Brian Tan
We extend the study of the occupancy fraction of the hard-core model in two novel directions. One direction gives a tight lower bound in terms of individual vertex degrees, extendi…
math.CO2024
On the occupancy fraction of the antiferromagnetic Ising model
Ewan Davies, Olivia LeBlanc
We study the maximum and minimum occupancy fraction of the antiferromagnetic Ising model in regular graphs. The minimizing problem is known to determine a computational threshold i…