Limits of action convergent graph sequences with unbounded $(p,q)$-norms
Abstract
The recently developed notion of action convergence by Backhausz and Szegedy unifies and generalises the dense (graphon) and local-global (graphing) convergences of graph sequences. This is done through viewing graphs as operators and examining their dynamical properties. Suppose is a sequence of operators representing graphs, Cauchy with respect to the action metric. If has uniformly bounded -norms where is any pair in , then Backhausz and Szegedy prove that has a limit operator which, moreover, must be self-adjoint and positivity-preserving. In the present work, we construct a large class of graph sequences whose only uniformly bounded -norm is the -norm, but which converge nonetheless. We show that the limit operators in this case are not unique, not self-adjoint, and need not be positivity-preserving. In particular, in the action convergence language, this means that the space of graphops is not compact. By identifying these multiple limits, we also demonstrate that -regularity is not invariant under weak equivalence, where is the eigenvalue of the identity function, when the identity function is an eigenfunction.
Keywords
Cite
@article{arxiv.2210.10720,
title = {Limits of action convergent graph sequences with unbounded $(p,q)$-norms},
author = {Aranka Hrušková},
journal= {arXiv preprint arXiv:2210.10720},
year = {2022}
}
Comments
29 pages, 4 figures