# Saturation of the quantum null energy condition in far-from-equilibrium systems

@article{Ecker2017SaturationOT, title={Saturation of the quantum null energy condition in far-from-equilibrium systems}, author={Christian Ecker and Daniel Grumiller and Wilke van der Schee and Philipp Stanzer}, journal={Physical Review D}, year={2017} }

The quantum null energy condition (QNEC) is a new local energy condition that a general quantum field theory (QFT) is believed to satisfy, relating the classical null energy condition (NEC) to the second functional derivative of the entanglement entropy in the corresponding null direction. We present the first series of explicit computations of QNEC in a strongly coupled QFT, using holography. We consider the vacuum, thermal equilibrium, a homogeneous far-from-equilibrium quench as well as a…

## 13 Citations

### Bulk matter and the boundary quantum null energy condition

- PhysicsJournal of High Energy Physics
- 2018

A bstractWe investigate the quantum null energy condition (QNEC) in holographic CFTs, focusing on half-spaces and particular classes of states. We present direct, and in certain cases…

### Quantum null energy condition and its (non)saturation in 2d CFTs

- PhysicsSciPost Physics
- 2019

We consider the Quantum Null Energy Condition (QNEC) for holographic
conformal field theories in two spacetime dimensions
(CFT_22).
We show that QNEC saturates for all states dual to vacuum solutions…

### Numerical Relativity, Holography and the Quantum Null Energy Condition

- Physics
- 2020

The quantum null energy condition (QNEC) is the only known consistent local energy condition in quantum theories. Contrary to the classical energy condition which are known to be violated in QFT,…

### Local Quantum Energy Conditions in Non-Lorentz-Invariant Quantum Field Theories.

- PhysicsPhysical review letters
- 2019

It is proved that the first example of local quantum energy conditions in quantum field theories that are not Lorentz invariant saturate for states in the field theory that are dual to vacuum solutions of three-dimensional Einstein gravity with a vanishing cosmological constant.

### Energy is Entanglement

- Physics
- 2018

We compute the local second variation of the von Neumann entropy of a region in theories with a gravity dual. For null variations our formula says that the diagonal part of the Quantum Null Energy…

### Entanglement Entropy from Numerical Holography

- Physics
- 2018

In this thesis I present numerical studies of entanglement entropy and the quantum null energy condition in strongly coupled far-from-equilibrium quantum states using holography. I give a careful…

### QNEC2 in deformed holographic CFTs

- PhysicsJournal of High Energy Physics
- 2021

We use the quantum null energy condition in strongly coupled two-dimensional field theories (QNEC2) as diagnostic tool to study a variety of phase structures, including crossover, second and first…

### Energy density from second shape variations of the von Neumann entropy

- PhysicsPhysical Review D
- 2018

We compute the local second variation of the von Neumann entropy of a region in theories with a gravity dual. For null variations our formula says that the diagonal part of the Quantum Null Energy…

### Can scale-dependent cosmology alleviate the H0 tension?

- Physics
- 2020

Scale-dependence is a common feature to all effective models of quantum gravity. In this paper, a cosmological model based on the scale-dependent scenario of gravity is presented. It is argued that…

### Holographic moving mirrors

- PhysicsClassical and Quantum Gravity
- 2021

Moving mirrors have been known as tractable setups modeling Hawking radiation from black holes. In this paper, motivated by recent developments regarding the black hole information problem, we…

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