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arXiv · 2402.10262

Explicit large $N$ von Neumann algebras from matrix models

Elliott Gesteau·Leonardo Santilli
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Abstract

We construct a large family of quantum mechanical systems that give rise to an emergent type III$_1$ von Neumann algebra in the large $N$ limit. Their partition functions are matrix integrals that appear in the study of various gauge theories. We calculate the real-time, finite temperature correlation functions in these systems and show that they are described by an emergent type III$_1$ von Neumann algebra at large $N$. The spectral density underlying this algebra is computed in closed form in terms of the eigenvalue density of a discrete matrix model. Furthermore, we explain how to systematically promote these theories to systems with a Hagedorn transition, and show that a type III$_1$ algebra only emerges above the Hagedorn temperature. Finally, we empirically observe in examples a correspondence between the space of states of the quantum mechanics and Calabi--Yau manifolds.

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Elliott Gesteau, Leonardo Santilli. 2024-02-15. Explicit large $N$ von Neumann algebras from matrix models. https://doi.org/10.4310/atmp.241031230051

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