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Related papers: Violations of the Null Energy Condition in QFT and…

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We examine the quantum null energy condition (QNEC) for a $2+1$-dimensional conformal field theory (CFT) at strong coupling in the background of a wormhole spacetime by employing the AdS/CFT correspondence. First, we numerically construct a…

High Energy Physics - Theory · Physics 2019-01-14 Akihiro Ishibashi , Kengo Maeda , Eric Mefford

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…

High Energy Physics - Theory · Physics 2018-07-04 Christian Ecker , Daniel Grumiller , Wilke van der Schee , Philipp Stanzer

Violation of the null energy condition plays an important role both in the general theory of relativity and quantum field theory in curved spacetimes. Over the years, it has been shown that the violation of the null energy condition leads…

General Relativity and Quantum Cosmology · Physics 2021-09-14 Susobhan Mandal

Quantum fields can notoriously violate the null energy condition (NEC). In a cosmological context, NEC violation can lead to, e.g., dark energy at late times with an equation-of-state parameter smaller than $-1$ and nonsingular bounces at…

General Relativity and Quantum Cosmology · Physics 2025-07-01 Elly Moghtaderi , Brayden R. Hull , Jerome Quintin , Ghazal Geshnizjani

The quantum null energy condition (QNEC) is a conjectured relation between a null version of quantum field theory energy and derivatives of quantum field theory von Neumann entropy. In some cases, divergences cancel between these two terms…

High Energy Physics - Theory · Physics 2018-02-21 Zicao Fu , Donald Marolf

The quantum null energy condition (QNEC) is a lower bound on the expectation value of the null-null component of the energy-momentum tensor in terms of null variations of the entanglement entropy. A stronger version of the QNEC (the primary…

High Energy Physics - Theory · Physics 2025-06-17 Tanay Kibe , Pratik Roy

The restricted quantum focusing conjecture (rQFC) plays a central role in an axiomatic formulation of semiclassical gravity. Since much hinges on its validity, it is imperative to subject the rQFC to rigorous tests in novel settings. Here…

High Energy Physics - Theory · Physics 2025-10-28 Victor Franken , Sami Kaya , François Rondeau , Arvin Shahbazi-Moghaddam , Patrick Tran

Explorations of the violation of null energy condition (NEC) in cosmology could enrich our understanding of the very early universe and the related gravity theories. Although a fully stable NEC violation can be realized in the ``beyond…

General Relativity and Quantum Cosmology · Physics 2022-10-24 Yong Cai , Ji Xu , Shuai Zhao , Siyi Zhou

The Quantum Null Energy Condition (QNEC) relates energy to the second variation of entropy in relativistic quantum field theory. We use the QNEC inequality to bound entanglement entropy in quenches. At early times the entanglement entropy…

High Energy Physics - Theory · Physics 2019-09-04 Márk Mezei , Julio Virrueta

Traversable wormhole solutions in General Relativity require exotic matter sources that violate the null energy condition (NEC), and such behavior maybe avoided in modified gravity. In this study, we analyze the energy conditions for…

General Relativity and Quantum Cosmology · Physics 2023-01-25 Anshuman Baruah , Parangam Goswami , Atri Deshamukhya

Traversable wormholes in General Relativity (GR) require exotic matter sources that violate the null energy condition (NEC), and such behavior may be avoided in modified gravity. Moreover, the concept of non-commutative geometry as a…

General Relativity and Quantum Cosmology · Physics 2022-10-18 Anshuman Baruah , Parangam Goswami , Atri Deshamukhya

Wormhole and time machine are very interesting objects in general relativity. However, they need exotic matters which are impossible in classical level to support them. But if we introduce the quantum effects of gravity into the…

General Relativity and Quantum Cosmology · Physics 2010-04-30 Li-Fang Li , Jian-Yang Zhu

The present article lies at the interface between gravity, a highly nonlinear phenomenon, and quantum field theory. The nonlinear field equations of Einstein permit the theoretical existence of classical wormholes. One of the fundamental…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Kamal K. Nandi , Yuan-Zhong Zhang , Nail G. Migranov

We study the consequences of Entanglement Wedge Nesting for CFTs with holographic duals. The CFT is formulated on an arbitrary curved background, and we include the effects of curvature-squared couplings in the bulk. In this setup we find…

High Energy Physics - Theory · Physics 2020-01-29 Chris Akers , Venkatesa Chandrasekaran , Stefan Leichenauer , Adam Levine , Arvin Shahbazi Moghaddam

We clarify the role of the oft-misunderstood Null Energy Condition (NEC) in the context of the current cosmological data. In particular, the NEC implies the sum of the total energy density and pressure satisfies $\rho_{tot}+P_{tot} \ge 0$;…

Cosmology and Nongalactic Astrophysics · Physics 2025-11-12 Robert R. Caldwell , Eric V. Linder

In the framework of the theory of general relativity, in order to obtain stable traversable wormholes, matter needs to violate the null energy condition. It is well known that the violation of the energy condition (EC) of matter leads to…

General Relativity and Quantum Cosmology · Physics 2024-03-22 Jianbo Lu , Shining Yang , Yan Liu , Yuying Zhang , Yu Liu

Field theories which violate the null energy condition (NEC) are of interest for the solution of the cosmological singularity problem and for models of cosmological dark energy with the equation of state parameter $w<-1$. We discuss the…

High Energy Physics - Theory · Physics 2008-11-26 I. Ya. Aref'eva , I. V. Volovich

The non-minimal coupling of scalar fields to gravity has been claimed to violate energy conditions, leading to exotic phenomena such as traversable wormholes, even in classical theories. In this work we adopt the view that the non-minimal…

High Energy Physics - Theory · Physics 2023-09-21 Jackson R. Fliss , Ben Freivogel , Eleni-Alexandra Kontou , Diego Pardo Santos

We 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 nonperturbative, calculations for both the diagonal and off-…

High Energy Physics - Theory · Physics 2018-09-26 Zuhair U. Khandker , Sandipan Kundu , Daliang Li

We study a cosmological scenario featuring an early phase of null energy condition (NEC) violation. Within this framework, we show that perturbative unitarity bounds place strong constraints on both the amplitude and the spectral tilt of…

High Energy Physics - Theory · Physics 2026-01-21 Pavel Petrov , Jianing Wang
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