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arXiv · 2605.14778

Fredholm Criteria for $G$-pseudodifferential Operators

Alexandre Baldare·Anton Yu. Savin·Elmar Schrohe
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Abstract

Let $G$ be a compact Lie group that acts smoothly on a closed manifold $M$. Using a general Simonenko principle, we derive a novel criterion for the Fredholm property of $G$-pseudodifferential operators acting on Sobolev spaces of sections of vector bundles over $M$. In case the group is finite, we obtain a further characterization of the Fredholm property of $G$-pseudodifferential operators in terms of the invertibility of suitable symbols.

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Alexandre Baldare, Anton Yu. Savin, Elmar Schrohe. 2026-05-14. Fredholm Criteria for $G$-pseudodifferential Operators. https://arxiv.org/abs/2605.14778

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