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arXiv · 2305.19463

Strong 1-boundedness, $L^2$-Betti numbers, algebraic soficity, and graph products

Ian Charlesworth·Rolando de Santiago·Ben Hayes·David Jekel·Srivatsav Kunnawalkam Elayavalli·Brent Nelson
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Abstract

We show that graph products of non trivial finite dimensional von Neumann algebras are strongly 1-bounded when the underlying *-algebra has vanishing first L2-Betti number. The proof uses a combination of the following two key ideas to obtain lower bounds on the Fuglede-Kadison determinant of matrix polynomials in a generating set: a notion called ''algebraic soficity'' for *-algebras allowing for the existence of Galois bounded microstates with asymptotically constant diagonals; a probabilistic construction of the authors of permutation models for graph independence over the diagonal.

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Ian Charlesworth, Rolando de Santiago, Ben Hayes, David Jekel, Srivatsav Kunnawalkam Elayavalli, Brent Nelson. 2023-05-31. Strong 1-boundedness, $L^2$-Betti numbers, algebraic soficity, and graph products. https://arxiv.org/abs/2305.19463

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