The relative solidity conjecture for relatively hyperbolic groups

From papers

Let GG be a group that is hyperbolic relative to a finite family of subgroups {H1,,Hn}\{H_1,\ldots,H_n\}. Denote by M=L(G)\mathcal M=\mathcal L(G) the von Neumann algebra corresponding to GG. Let pMp\in\mathcal M be a nonzero projection and let ApMp\mathcal A\subseteq p\mathcal M p be a von Neumann subalgebra whose relative commutant ApMp\mathcal A'\cap p\mathcal M p has no amenable direct summand. Relative solidity conjecture. There is some 1in1\leq i\leq n such that a corner of A\mathcal A intertwines into L(Hi)\mathcal L(H_i) inside M\mathcal M, in the sense of Popa; that is, AML(Hi)\mathcal A\prec_{\mathcal M}\mathcal L(H_i). This concerns the structure of commuting subalgebras of group von Neumann algebras associated with relatively hyperbolic groups; the supplied text gives no resolution status for the conjecture.

Progress summary

Nothing recorded yet. Refresh searches the literature and the public web for attempts on this problem, and writes the first summary here.

Sources & referencesView supporting material

Primary source

Juan Felipe Ariza Mejia, Dulanji Nikethani Amaraweera, Ionut Chifan and Krishnendu Khan, “Relative solidity results and their applications to computations of some II_1 factor invariants”, arXiv:2509.19481 (2025).

Solutions 0

No solutions have been posted yet.