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arXiv · 1705.01128

Emergent spacetime & Quantum Entanglement in Matrix theory

Vatche Sahakian·Yossathorn Tawabutr·Cynthia Yan
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Abstract

In the context of the Bank-Fishler-Shenker-Susskind Matrix theory, we analyze a spherical membrane in light-cone M theory along with two asymptotically distant probes. In the appropriate energy regime, we find that the membrane behaves like a smeared Matrix black hole; and the spacetime geometry seen by the probes can become non-commutative even far away from regions of Planckian curvature. This arises from non-linear Matrix interactions where fast matrix modes lift a flat direction in the potential -- akin to the Paul trap phenomenon in atomic physics. In the regime where we do have a notion of emergent spacetime, we show that there is non-zero entanglement entropy between supergravity modes on the membrane and the probes. The computation can easily be generalized to other settings, and this can help develop a dictionary between entanglement entropy and local geometry -- similar to Ryu-Takayanagi but instead for asymptotically flat backgrounds.

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Vatche Sahakian, Yossathorn Tawabutr, Cynthia Yan. 2017-05-02. Emergent spacetime & Quantum Entanglement in Matrix theory. https://doi.org/10.1007/jhep08(2017)140

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