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arXiv · 2511.09076

Upper Bounds for $s$-Distance Subspaces

LiXia Wang·Ke Ye
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Abstract

As a generalization of equiangular lines, equiangular subspaces were first systematically studied by Balla, Dr\"{a}xler, Keevash and Sudakov in 2017. In this paper, we extend their work to $s$-distance subspaces, i.e., to sets of $k$-dimensional subspaces in $\mathbb{R}^n$ whose pairwise distances take $s$ distinct values. We establish upper bounds on the maximum cardinality of such sets. In particular, our bounds generalize and improve results of Balla and Sudakov.

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LiXia Wang, Ke Ye. 2025-11-12. Upper Bounds for $s$-Distance Subspaces. https://arxiv.org/abs/2511.09076

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