Tight frames over the quaternions and equiangular lines
Functional Analysis
2025-08-29 v3 Information Theory
math.IT
Representation Theory
Abstract
We show that much of the theory of finite tight frames can be generalised to vector spaces over the quaternions. This includes the variational characterisation, group frames, and the characterisations of projective and unitary equivalence. We are particularly interested in sets of equiangular lines (equi-isoclinic subspaces) and the groups associated with them, and how to move them between the spaces , and . We discuss what the analogue of Zauner's conjecture for equiangular lines in might be.
Cite
@article{arxiv.2006.06126,
title = {Tight frames over the quaternions and equiangular lines},
author = {Shayne Waldron},
journal= {arXiv preprint arXiv:2006.06126},
year = {2025}
}