English

A Switching for all Strongly Regular Collinearity Graphs From Polar Spaces

Combinatorics 2017-08-01 v3

Abstract

We describe a general construction of strongly regular graphs from the collinearity graph of a finite classical polar spaces of rank at least 33 over a finite field of order qq. We show that these graphs are non-isomorphic to the collinearity graphs and have the same parameters. To our knowledge for most of these parameters these graphs are new as the collinearity graphs were the only known examples.

Keywords

Cite

@article{arxiv.1606.05898,
  title  = {A Switching for all Strongly Regular Collinearity Graphs From Polar Spaces},
  author = {Ferdinand Ihringer},
  journal= {arXiv preprint arXiv:1606.05898},
  year   = {2017}
}

Comments

11 pages, older version published in the Journal of Algebraic Combinatorics, fixed a typo in Lemma 3.5 and added a comment due to Kantor

R2 v1 2026-06-22T14:28:49.491Z