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Related papers: Averaged null energy condition in Loop Quantum Cos…

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Firstly, we review the pointwise and averaged energy conditions, the quantum inequality and the notion of the ``volume integral quantifier'', which provides a measure of the ``total amount'' of energy condition violating matter. Secondly,…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Francisco S. N. Lobo

The dynamics of interacting dark energy model in loop quantum cosmology (LQC) is studied in this paper. The dark energy has a constant equation of state $w_x$ and interacts with dark matter through a form $3cH(\rho_x+\rho_m)$. We find for…

Astrophysics · Physics 2011-07-13 Puxun Wu , Shuang Nan Zhang

The averaged null energy condition has known violations for quantum fields in curved space, even if one considers only achronal geodesics. Many such examples involve rapid variation in the stress-energy tensor in the vicinity of the…

General Relativity and Quantum Cosmology · Physics 2014-11-20 Douglas Urban , Ken D. Olum

By incorporating quantum aspects of gravity, Loop Quantum Cosmology (LQC) provides a self-consistent extension of the inflationary scenario, allowing for modifications in the primordial inflationary power spectrum with respect to the…

Cosmology and Nongalactic Astrophysics · Physics 2019-11-01 Micol Benetti , Leila Graef , Rudnei O. Ramos

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

Non-perturbative corrections from loop quantum cosmology (LQC) to the scalar matter sector is already known to imply inflation. We prove that the LQC modified scalar field generates exponential inflation in the small scale factor regime,…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Ghanashyam Date , Golam Mortuza Hossain

It is a very well known fact that the energy conditions concerning Lorentzian wormhole (WH) solutions of Einstein equations are violated. Consequently, attempts to avoid the violation of the energy conditions constitutes one of the main…

High Energy Physics - Theory · Physics 2012-08-01 Everton M. C. Abreu , Nélio Sasaki

Phenomenological effect of the super-inflation in loop quantum cosmology (LQC) is discussed. We investigate the case that the Universe is filled with the interacting field between massive scalar field and radiation. Considering the damping…

General Relativity and Quantum Cosmology · Physics 2013-11-28 Kui Xiao , Xiao-Kai He , Jian-Yang Zhu

We describe the different possibilities that a simple and apparently quite harmless classical scalar field theory provides to violate the energy conditions. We demonstrate that a non-minimally coupled scalar field with a positive curvature…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Carlos Barcelo , Matt Visser

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 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 last decades have witnessed an unprecedented advancement in our knowledge of the large scale universe. In particular, increasingly accurate cosmological observations have allowed us to discover a form of "dark energy", which presently…

General Relativity and Quantum Cosmology · Physics 2022-04-11 Eduardo Amancio Barbosa Oliveira

Loop quantum cosmology (LQC) is very powerful to deal with the behavior of early universe. And the effective loop quantum cosmology gives a successful description of the universe in the semiclassical region. We consider the apparent horizon…

General Relativity and Quantum Cosmology · Physics 2010-04-15 Li-Fang Li , Jian-Yang Zhu

The averaged null energy condition (ANEC) requires that the integral over a complete null geodesic of the stress-energy tensor projected onto the geodesic tangent vector is never negative. This condition is sufficient to prove many…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Noah Graham , Ken D. Olum

Proposing smooth initial conditions is one of the most important tasks in quantum cosmology. On the other hand, the low-energy effective action, appearing in the semiclassical path integral, can get nontrivial quantum corrections near…

General Relativity and Quantum Cosmology · Physics 2018-11-07 Suddhasattwa Brahma , Dong-han Yeom

Following the recent theory of Lovelock-Brans-Dicke gravity, we continue to investigate the conditions to support traversable wormholes by the gravitational effects of spacetime parity and topology, which arise from the nonminimal couplings…

General Relativity and Quantum Cosmology · Physics 2016-01-08 David Wenjie Tian

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

It is shown that the averaged null energy condition is fulfilled for a dense, translationally invariant set of vector states in any local quantum field theory in two-dimensional Minkowski spacetime whenever the theory has a mass gap and…

Mathematical Physics · Physics 2015-06-26 Rainer Verch

The primordial Universe can be used as a laboratory to set constraints on quantum gravity. In the framework of Loop Quantum Cosmology, we show that such a proposal for quantum gravity not only solves for the big bang singularity issue but…

General Relativity and Quantum Cosmology · Physics 2012-06-08 Julien Grain

Quantum gravity is expected to be necessary in order to understand situations where classical general relativity breaks down. In particular in cosmology one has to deal with initial singularities, i.e. the fact that the backward evolution…

General Relativity and Quantum Cosmology · Physics 2016-10-19 Martin Bojowald