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arXiv · 2401.04945

Soficity for group actions on sets and applications

David Gao·Srivatsav Kunnawalkam Elayavalli·Gregory Patchell
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Abstract

In this article we develop a notion of soficity for actions of countable groups on sets. We show two equivalent perspectives, several natural properties and examples. Notable examples include arbitrary actions of both amenable groups and free groups, and actions of sofic groups with locally finite stabilizers. As applications we prove soficity for generalized wreath products (and amalgamated free generalized wreath products) of sofic groups where the underlying group action is sofic. This generalizes the result of Hayes and Sale [HS18], and proves soficity for many new families of groups.

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David Gao, Srivatsav Kunnawalkam Elayavalli, Gregory Patchell. 2024-01-10. Soficity for group actions on sets and applications. https://doi.org/10.1007/s40687-025-00526-6

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