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arXiv · 2007.06467

Crossing a large-$N$ phase transition at finite volume

Abstract

The existence of phase-separated states is an essential feature of infinite-volume systems with a thermal, first-order phase transition. At energies between those at which the phase transition takes place, equilibrium homogeneous states are either metastable or suffer from a spinodal instability. In this range the stable states are inhomogeneous, phase-separated states. We use holography to investigate how this picture is modified at finite volume in a strongly coupled, four-dimensional gauge theory. We work in the planar limit, $N \to \infty$, which ensures that we remain in the thermodynamic limit. We uncover a rich set of inhomogeneous states dual to lumpy black branes on the gravity side, as well as first- and second-order phase transitions between them. We establish their local (in)stability properties and show that fully non-linear time evolution in the bulk takes unstable states to stable ones.

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Yago Bea, Oscar J. C. Dias, Thanasis Giannakopoulos, David Mateos, Mikel Sanchez-Garitaonandia, Jorge E. Santos, Miguel Zilhao. 2020-07-13. Crossing a large-$N$ phase transition at finite volume. https://doi.org/10.1007/jhep02(2021)061

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