On 2-transitive sets of equiangular lines

TL;DR

This paper characterizes finite sets of equiangular lines in unitary spaces where the stabilizer group acts 2-transitively with a regular normal subgroup, advancing understanding of symmetry in these configurations.

Contribution

It provides a classification of such equiangular line sets based on their symmetry properties under the stabilizer group action.

Findings

Complete characterization of 2-transitive equiangular line sets

Identification of conditions for the stabilizer group action

Insights into symmetry and structure of equiangular lines

Abstract

All finite sets of equiangular lines spanning finite-dimensional unitary spaces are determined for which the action on the lines of the set-stabilizer in the unitary group is 2-transitive with a regular normal subgroup.