2025/10/09 by Esson, Jack, Kastis, Eleftherios, Schulze, Bernd
#52A21 (secondary) #52C25 (primary) 05C22 #Combinatorics (math.CO) #FOS: Mathematics
paper · doi:10.48550/arxiv.2510.08128
This paper establishes combinatorial characterisations of forced-symmetric and forced-periodic rigidity (under a fixed lattice) of bar-joint frameworks in non-Euclidean normed planes. In ℓq-planes for q∈(1,∞)\backslash\2\, we prove characterisations for periodic rigidity and finite reflectionally-symmetric rigidity. We also characterise symmetric rigidity in this space with respect to the orientation-reversing wallpaper group ℤ2\rtimesCs, otherwise known as pm in crystallography. In the ℓ1 and ℓ_∞-planes, we provide characterisations for periodic rigidity and ℤ2\rtimesCs-symmetric rigidity. All of these characterisations are proved by inductive constructions involving Henneberg-type graph operations.