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arXiv · 2607.17670

$L^2$-cohomology and deformations of the left regular representation

Christoph Gamm·Andreas Thom
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Abstract

We study deformations of unitary representations $\pi\colon G\to U(H)$ whose coefficients lie in the Hilbert-Schmidt ideal $HS(H)\subset B(H)$. Interesting applications arise for the left-regular representation of surface groups and, more generally, cocompact lattices in the automorphism group of a Fuchsian building of conformal dimension $<2$.

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Christoph Gamm, Andreas Thom. 2026-07-20. $L^2$-cohomology and deformations of the left regular representation. https://arxiv.org/abs/2607.17670

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