The Atiyah Conjecture with rational coefficients

Let GG be a torsion-free group, let m,nm,n be positive integers, and let AMm,n(QG)A\in M_{m,n}(\mathbb{Q}G). Write rA ⁣:N(G)mN(G)nr_A\colon \mathcal{N}(G)^m\to\mathcal{N}(G)^n for right multiplication by AA, and let dimN(G)\dim_{\mathcal{N}(G)} denote von Neumann dimension. Atiyah Conjecture. The group GG satisfies the Atiyah Conjecture with rational coefficients if, for every such matrix AA,

dimN(G)(ker(rA ⁣:N(G)mN(G)n))Z.\dim_{\mathcal{N}(G)}\bigl(\ker(r_A\colon \mathcal{N}(G)^m\to\mathcal{N}(G)^n)\bigr)\in\mathbb{Z}.

This is the integrality assertion needed in the construction of the L2L^2-torsion polytope. The supplied text gives the definition but no resolution status for the conjectural condition itself.

Sources & referencesView supporting material

Primary source

Florian Funke, “The L^2-torsion polytope of amenable groups”, arXiv:1704.07164 (2019).

Progress summary

Never refreshed

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

Solutions 0

No solutions have been posted yet.