Involutions and angles between subspaces

Jean-Christophe Bourin; Eun-Young Lee

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arXiv · 2602.19599

Involutions and angles between subspaces

Jean-Christophe Bourin·Eun-Young Lee

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Abstract

We provide a complete structure theorem for involutory matrices. This yields a new approach to principal angles between subspaces and provide a series of nice formulae for these angles.

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Jean-Christophe Bourin, Eun-Young Lee. 2026-02-23. Involutions and angles between subspaces. https://arxiv.org/abs/2602.19599

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