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arXiv · 2411.18471

Strongly Coupled PT-Symmetric Models in Holography

Daniel Arean·David Garcia-Fariña·Karl Landsteiner
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Abstract

Non-Hermitian quantum field theories are a promising tool to study open quantum systems. These theories preserve unitarity if PT-symmetry is respected, and in that case an equivalent Hermitian description exists via the so-called Dyson map. Generically, PT-symmetric non-Hermitian theories can also feature phases where PT-symmetry is broken and unitarity is lost. We review the construction of holographic duals to strongly coupled PT-symmetric quantum field theories and the study of their phase diagram. We next focus on spacetime-dependent non-Hermitian couplings: non-Hermitian quenches and lattices. They violate the null energy condition in the gravity dual. The lattices realize phases supporting an imaginary current that breaks PT-symmetry spontaneously. Remarkably, these non-Hermitian lattices flow to a PT-symmetric fixed point in the IR.

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Daniel Arean, David Garcia-Fariña, Karl Landsteiner. 2024-11-27. Strongly Coupled PT-Symmetric Models in Holography. https://arxiv.org/abs/2411.18471

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