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arXiv · 2109.13381

Dynamical Symmetry and the Thermofield State at Large $N$

Antal Jevicki·Xianlong Liu·Junggi Yoon·Junjie Zheng
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Abstract

We discus Thermofield Double QFT at real time, in the large $N$ limit. First, we establish a (dynamical) symmetry which we argue holds in general on the real time portion of the Schwinger-Kelydish contour. At large $N$ this symmetry is seen to generate a one parameter degeneracy of stationary collective solutions. The construction is explicitly worked out on the example of $O(N)$ vector QFT. As a nontrivial application we describe construction of the corresponding (large $N$) Thermofield Double State in real time collective formalism.

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Antal Jevicki, Xianlong Liu, Junggi Yoon, Junjie Zheng. 2021-09-27. Dynamical Symmetry and the Thermofield State at Large $N$. https://doi.org/10.3390/universe8020114

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