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Related papers: Causal Entropy Bound for Non-Singular Cosmologies

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I review some basic facts about entropy bounds in general and about cosmological entropy bounds. Then I review the Causal Entropy Bound, the conditions for its validity and its application to the study of cosmological singularities. This…

High Energy Physics - Theory · Physics 2008-11-26 Ram Brustein

The causal entropy bound (CEB) is confronted with recent explicit entropy calculations in weakly and strongly coupled conformal field theories (CFTs) in arbitrary dimension $D$. For CFT's with a large number of fields, $N$, the CEB is found…

High Energy Physics - Theory · Physics 2009-11-07 R. Brustein , S. Foffa , G. Veneziano

In discussions of Bousso's Covariant Entropy Bound, the Null Energy Condition is always assumed, as a sufficient {\em but not necessary} condition which helps to ensure that the entropy on any lightsheet shall necessarily be finite. The…

High Energy Physics - Theory · Physics 2010-12-23 Brett McInnes

Entropy bounds render quantum corrections to the cosmological constant $\Lambda$ finite. Under certain assumptions, the natural value of $\Lambda$ is of order the observed dark energy density $\sim 10^{-10} {\rm eV}^4$, thereby resolving…

High Energy Physics - Theory · Physics 2008-11-26 Stephen D. H. Hsu

An isotropic and homogeneous cosmological model with a source of dark energy is studied. That source is simulated with a viscous relativistic fluid with minimal causal correction. In this model the restrictions on the parameters coming from…

General Relativity and Quantum Cosmology · Physics 2017-04-20 Carlos E. Laciana

After discussing some old (and not-so-old) entropy bounds both for isolated systems and in cosmology, I will argue in favour of a "Hubble entropy bound" holding in the latter context. I will then apply this bound to recent developments in…

High Energy Physics - Theory · Physics 2007-05-23 G. Veneziano

It was shown in a previous work that, for systems in which the entropy is an extensive function of the energy and volume, the Bekenstein and the holographic entropy bounds predict new results. In this paper, we go further and derive…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Gilad Gour

Bell's theorem shows that our intuitive understanding of causation must be overturned in light of quantum correlations. Nevertheless, quantum mechanics does not permit signalling and hence a notion of cause remains. Understanding this…

Quantum Physics · Physics 2016-10-19 Mirjam Weilenmann , Roger Colbeck

The causal entropic principle aims to predict the unexpectedly small value of the cosmological constant Lambda using a weighting by entropy increase on causal diamonds. The original work assumed a purely isotropic and homogeneous cosmology.…

General Relativity and Quantum Cosmology · Physics 2012-01-20 Daniel Phillips , Andreas Albrecht

The identification of a causal-connection scale motivates us to propose a new covariant bound on entropy within a generic space-like region. This "causal entropy bound", scaling as the square root of EV, and thus lying around the geometric…

High Energy Physics - Theory · Physics 2009-10-31 R. Brustein , G. Veneziano

A matter bouncing entropy-corrected cosmological model has been suggested. The model allows only positive curvature with negative pressure and no violation of the null energy condition. The result obtained in this paper is supported by some…

General Relativity and Quantum Cosmology · Physics 2022-10-12 Nasr Ahmed , Tarek M. Kamel , Mohamed I Nouh

We use rigorous non-equilibrium thermodynamic arguments to prove (i) the residual entropy of any system is bounded below by the experimentally (calorimetrically) determined absolute temperature entropy, which itself is bounded below by the…

Statistical Mechanics · Physics 2011-06-13 P. D. Gujrati

The paper is a brief informal introduction to C*-algebraic foundations of causal contextual subquantum theories. In particular, it is explained how the contextuality property (which is a necessary consistency condition of all causal…

Quantum Physics · Physics 2007-05-23 Micho Durdevich

Assuming the Bousso bound, we prove a singularity theorem: if the light rays entering a hyperentropic region contract, then at least one light ray must be incomplete. "Hyperentropic" means that the entropy of the region exceeds the…

High Energy Physics - Theory · Physics 2022-06-22 Raphael Bousso , Arvin Shahbazi-Moghaddam

Bousso's entropy bound is a conjecture that the entropy through a null hypersurface emanating from a two-dimensional surface with a nonpositive expansion is bounded by the area of that two-dimensional surface. We investigate the validity of…

General Relativity and Quantum Cosmology · Physics 2023-03-31 Takamasa Kanai , Kimihiro Nomura , Daisuke Yoshida

We present a comprehensive study of cosmological singularities within the framework of Covariant Extrinsic Gravity (CEG), addressing both the initial Big Bang singularity and potential finite-time future singularities. Through detailed…

General Relativity and Quantum Cosmology · Physics 2025-04-08 R. Jalalzadeh , S. Jalalzadeh , Y. Heydarzade

In a recent article entitled "A simple explanation of the quantum violation of a fundamental inequality," Cabello proposes a condition on a class of probabilistic models that, he claims, gives the same bound on contextuality for the KCBS…

Quantum Physics · Physics 2012-10-25 Joe Henson

We present a proposal to relate the de Sitter Conjecture (dSC) to the Covariant Entropy Bound (CEB). By assuming an early phase of accelerated expansion where the CEB is satisfied, we take into account a contribution from extra-dimensions…

High Energy Physics - Theory · Physics 2021-07-29 Dibya Chakraborty , Cesar Damian , Alberto Gonzalez Bernal , Oscar Loaiza-Brito

The energy conditions play an important role in the understanding of several properties of the Universe, including the current accelerating expansion phase and the possible existence of the so-called phantom fields. We show that the…

Astrophysics · Physics 2009-06-23 M. P. Lima , S. Vitenti , M. J. Reboucas

Probably not, because there are lots of manifestly unanthropic ways of producing entropy. We demonstrate that the Causal Entropic Principle (CEP), as a replacement for the anthropic principle to explain the properties of the observed…

High Energy Physics - Theory · Physics 2008-12-05 Irit Maor , Thomas W. Kephart , Lawrence M. Krauss , Y. Jack Ng , Glenn D. Starkman
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