A Remark on the First Eigenvalue of the Laplace Operator on 1-forms for Compact Inner Symmetric Spaces

Jean-Louis Milhorat

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arXiv · 2204.02806

A Remark on the First Eigenvalue of the Laplace Operator on 1-forms for Compact Inner Symmetric Spaces

Jean-Louis Milhorat

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Abstract

We remark that on a compact inner symmetric space $G/K$, indowed with the Riemmannian metric given by the Killing form of $G$ signed-changed, the first (non-zero) eigenvalue of the Laplace operator on $1$-forms is the Casimir eigenvalue of the highest either long or short root of $G$, according as the highest weight of the isotropy representation is long or short. Some results for the first (non-zero) eigenvalue on functions are derived. This is a revision of the first version of the preprint: a non correct statement about the spectrum on functions has been reviewed.

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Jean-Louis Milhorat. 2022-04-06. A Remark on the First Eigenvalue of the Laplace Operator on 1-forms for Compact Inner Symmetric Spaces. https://arxiv.org/abs/2204.02806

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