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The holographic principle, considered in a semiclassical setting, is shown to have direct consequences on physics at a fundamental level. In particular, a certain relation is pointed out to be the expression of holography in basic…

General Relativity and Quantum Cosmology · Physics 2011-02-03 Alessandro Pesci

To explain the acceleration of the cosmological expansion researchers have considered an unusual form of mass-energy generically called dark energy. Dark energy has a ratio of pressure over mass density which obeys $w=p/\rho <-1/3$. This…

High Energy Physics - Theory · Physics 2008-12-19 Max Chaves , Douglas Singleton

In this paper, we derive some new invariant solutions of dark energy models in cylindrically symmetric space-time. To quantify the deviation of pressure from isotropy, we introduce three different time dependent skewness parameters along…

General Relativity and Quantum Cosmology · Physics 2014-09-10 Anil Kumar Yadav , Ahmad T Ali

As we now know, there are indeed at least two major difficulties with General Relativity (GR). The first one is related with its incompatibility with quantum mechanics, in the absence of a widely accepted consistent theory that combines the…

General Physics · Physics 2015-06-05 Ram Gopal Vishwakarma

The dark energy problem may have a simple solution in the model of cosmology based on the space-time interaction hypothesis. The hypothesis throws light on the nature of time (see Time-Transcendence-Truth, Monograph published in 2006).

General Physics · Physics 2020-02-11 S. C. Tiwari

Recently, Verlinde discussed that gravity can be understood as an entropic force caused by changes in the information associated with the positions of material bodies. In the Verlinde's argument, the area law of the black hole entropy plays…

General Relativity and Quantum Cosmology · Physics 2010-05-19 Ahmad Sheykhi

Light received from a cosmological source is redshifted with an apparent loss of energy, a problem first pointed out by Edwin Hubble in 1936. A new type of energy called Hubble Energy is introduced to restore the principle of energy…

General Physics · Physics 2007-05-23 Alasdair Macleod

A cosmological model of dark energy interacting with dark matter and another general component of the universe is investigated. We found general constraints on these models imposing an accelerated expansion. The same is also studied in the…

High Energy Physics - Phenomenology · Physics 2008-11-26 Norman Cruz , Samuel Lepe , Francisco Pena

In the context of models where the dark energy density $\rD$ is a random variable, anthropic selection effects may explain both the "old" cosmological constant problem and the "time coincidence". We argue that this type of solution to both…

Astrophysics · Physics 2009-11-07 J. Garriga , A. Vilenkin

Dark solitons are common topological excitations in a wide array of nonlinear waves. The dark soliton excitation energy, crucial for exploring dark soliton dynamics, is necessarily calculated in a renormalized form due to its existence on a…

Pattern Formation and Solitons · Physics 2020-06-24 Li-Chen Zhao , Yan-Hong Qin , Wenlong Wang , Zhan-Ying Yang

We examine the consequences of a universe with a non-constant cosmological term in Einstein's equations and find that the Bianchi identities reduce to the first law of thermodynamics when cosmological term is identified as being…

General Relativity and Quantum Cosmology · Physics 2008-09-04 Richard T Hammond , Terry Pilling

A huge amount of good quality data converges towards the picture of a spatially flat universe undergoing the today observed phase of accelerated expansion. This new observational trend is commonly addressed as Precision Cosmology. Despite…

General Relativity and Quantum Cosmology · Physics 2008-12-02 S. Capozziello

We formulate power-law holographic dark energy, which is a modified holographic dark energy model based on the extended entropy relation arising from the consideration of state mixing between the ground and the excited ones in the…

General Relativity and Quantum Cosmology · Physics 2022-05-25 Eirini C. Telali , Emmanuel N. Saridakis

The dominance of dark energy in the universe has necessitated the introduction of a repulsive gravity source to make q0 negative. The models for dark energy range from a simple lambda-term to quintessence, Chaplygin gas, etc. We look at the…

General Physics · Physics 2011-09-12 C. Sivaram , Kenath Arun , R. Nagaraja

We investigate Kaniadakis-holographic dark energy by confronting it with observations. We perform a Markov Chain Monte Carlo analysis using cosmic chronometers, supernovae type Ia, and Baryon Acoustic Oscillations data. Concerning the…

Cosmology and Nongalactic Astrophysics · Physics 2022-02-09 A. Hernández-Almada , Genly Leon , Juan Magaña , Miguel A. García-Aspeitia , V. Motta , Emmanuel N. Saridakis , Kuralay Yesmakhanova

It is nowadays clear that General Relativity cannot be the definitive theory of Gravitation due to several shortcomings that come out both from theoretical and experimental viewpoints. At large scales (astrophysical and cosmological) the…

General Relativity and Quantum Cosmology · Physics 2009-10-02 S. Capozziello , M. De Laurentis , M. Francaviglia , S. Mercadante

We present a model that offers an explanation for the presence of (Dark Matter and) Dark Energy in the universe. A key idea is to express the volume form of the Lorentzian metric on space-time in terms of a positive function of a new scalar…

General Relativity and Quantum Cosmology · Physics 2026-01-12 Ali H. Chamseddine , Jürg Fröhlich

Starting from the revelation of the nature of inertial forces, this article discusses the subdivision of the basic physical concept of space-time and raises questions about the metric of standard cosmology. A new form of particle dynamics…

High Energy Physics - Theory · Physics 2024-06-25 ChiYi Chen

Cosmological constant a.k.a. dark energy problem is considered to be one major challenge in modern cosmology. Here we present a model where large scale structure formation causes spatially-flat FRW universe to fragment into numerous `FRW…

Astrophysics · Physics 2007-09-24 Golam Mortuza Hossain

The origin of the dark energy which is assumed to be responsible for the observed accelerated expansion of the universe still remains a scientific dilemma. Here we propose a tentative origin for this energy, if it is coming from a…

General Relativity and Quantum Cosmology · Physics 2015-06-23 N. Riazi , Sh. Assyyaee