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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 violations of the Null Energy Condition (NEC) in Quantum Field Theory (QFT) and their implications. For the first part of the project, we examine these violations for classes of already known and novel (first discussed here) QFT…

High Energy Physics - Theory · Physics 2018-06-04 Dimitrios Krommydas

We propose a universal inequality that unifies the Bousso bound with the classical focussing theorem. Given a surface $\sigma$ that need not lie on a horizon, we define a finite generalized entropy $S_\text{gen}$ as the area of $\sigma$ in…

High Energy Physics - Theory · Physics 2016-07-06 Raphael Bousso , Zachary Fisher , Stefan Leichenauer , and Aron C. Wall

A new attempt is demonstrated that QFTs can be UV finite if they are viewed as the low energy effective theories of a fundamental underlying theory (that is complete and well-defined in all respects) according to the modern standard point…

High Energy Physics - Theory · Physics 2007-05-23 Jifeng Yang

We derive new families of quantum null energy inequalities (QNEIs), i.e. bounds on integrated null energy, in quantum field theories in two and higher dimensions. These are universal, state-independent lower bounds on semi-local integrals…

High Energy Physics - Theory · Physics 2026-04-17 Jackson R. Fliss , Andrew Rolph

A new approach is demonstrated that QFTs can be UV finite if they are viewed as the low energy effective theories of a fundamental underlying theory (that is complete and well-defined in all respects) according to the nowaday's standard…

High Energy Physics - Theory · Physics 2008-02-03 Jifeng Yang

Quantum energy inequalities (QEIs) express restrictions on the extent to which weighted averages of the renormalized energy density can take negative expectation values within a quantum field theory. Here we derive, for the first time, QEIs…

General Relativity and Quantum Cosmology · Physics 2019-02-13 Christopher J. Fewster , Eleni-Alexandra Kontou

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

In has been recently shown [1] that in Dirac's hole theory the vacuum state is not the minimum energy state but that there exist quantum states with less energy than that of the vacuum state. In this paper we extend this discussion to…

Quantum Physics · Physics 2008-11-26 Dan Solomon

In general relativity, the energy conditions are invoked to restrict general energy-momentum tensors $T_{\mu\nu}$ in different frameworks, and to derive general results that hold in a variety of general contexts on physical grounds. We show…

Astrophysics · Physics 2008-11-26 J. Santos , J. S. Alcaniz , N. Pires , M. J. Reboucas

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 Condition is saturated in every state, thus…

High Energy Physics - Theory · Physics 2018-10-17 Stefan Leichenauer , Adam Levine , Arvin Shahbazi-Moghaddam

Starting from an (unknown) quantum gravitational model, one can invoke a sequence of approximations to progressively arrive at quantum field theory (QFT) in curved spacetime, QFT in flat spacetime, nonrelativistic quantum mechanics and…

General Relativity and Quantum Cosmology · Physics 2011-09-15 T. Padmanabhan , T. Roy Choudhury

In quantum theory it is generally assumed that there exists a special state called the vacuum state and that this state is a lower bound to the energy. However it has recently been demonstrated that this is not necessarily the case for some…

Quantum Physics · Physics 2009-04-21 Dan Solomon

Quantum field theory violates all the classical energy conditions of general relativity. Nonetheless, it turns out that quantum field theories satisfy remnants of the classical energy conditions, known as Quantum Energy Inequalities (QEIs),…

General Relativity and Quantum Cosmology · Physics 2012-08-28 Christopher J. Fewster

The weak energy condition is known to fail in general when applied to expectation values of the the energy momentum tensor in flat space quantum field theory. It is shown how the usual counter arguments against its validity are no longer…

High Energy Physics - Theory · Physics 2009-10-30 J. I. Latorre , H. Osborn

We define a new dynamical variable, the relative existence e, in terms of space and time. Taking it as a generalized positional coordinate, we show that for conservative systems the canonically conjugated momentum is identified as the…

Quantum Physics · Physics 2007-05-23 C. G. S. Costa

A foundation of quantum mechanics based on the concepts of focusing and symmetry is proposed. Focusing is connected to c-variables - inaccessible conceptually derived variables; several examples of such variables are given. The focus is…

Quantum Physics · Physics 2023-10-30 Inge S. Helland

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

Today's quantum field theory (QFT) relies heavenly on canonical quantization (CQ), which fails for $\varphi^4_4$ leading only to a "free" result. Affine quantization (AQ), an alternative quantization procedure, leads to a "non-free" result…

General Physics · Physics 2021-08-25 John R. Klauder

In quantum field theory it is generally assumed that there is a lower bound to the energy of a quantum state. Here, it will be shown that there is no lower bound to the energy of physical states in QED in a manifestly covariant gauge.

Quantum Physics · Physics 2007-05-23 Dan Solomon