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arXiv · 2601.22411

Quasihomomorphisms to real algebraic groups

Sami Douba·Francesco Fournier-Facio·Sam Hughes·Simon Machado
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Abstract

A quasihomomorphism is a map that satisfies the homomorphism relation up to bounded error. Fujiwara and Kapovich proved a rigidity result for quasihomomorphisms taking values in discrete groups, showing that all quasihomomorphisms can be built from homomorphisms and sections of bounded central extensions. We study quasihomomorphisms with values in real linear algebraic groups, and prove an analogous rigidity theorem.

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Sami Douba, Francesco Fournier-Facio, Sam Hughes, Simon Machado. 2026-01-29. Quasihomomorphisms to real algebraic groups. https://arxiv.org/abs/2601.22411

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