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arXiv · 2502.00256

Adapted almost invariant sets and splittings of groups

Peter Scott·Gadde Swarup
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Abstract

We prove relative versions of many earlier results about almost invariant sets and splittings of groups. In particular, we prove a relative version of the algebraic torus theorem, and we prove the existence and uniqueness of relative versions of algebraic regular neighbourhoods and of JSJ decompositions.

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Peter Scott, Gadde Swarup. 2025-02-01. Adapted almost invariant sets and splittings of groups. https://arxiv.org/abs/2502.00256

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