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Related papers: Turnaround in Cyclic Cosmology

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Among many models which can describe the bouncing cosmology, A matter bounce scenario that is deformed by a running vacuum model of dark energy (RVM-DE) has been interested. In this research, I show that a class of RVM-CDM (cold dark…

General Relativity and Quantum Cosmology · Physics 2022-09-13 A. Khodam-Mohammadi

Our Universe has multiple examples of unexplained gravitational losses in black holes and neutron stars. As all of the space is squeezed out, nucleons are not easily compressible further. Gravitational loss will allow galactic black holes…

Astrophysics · Physics 2024-12-24 David E. Rosenberg

I briefly outline a new physical interpretation to the average cosmological parameters for an inhomogeneous universe with backreaction. The variance in local geometry and gravitational energy between ideal isotropic observers in bound…

Cosmology and Nongalactic Astrophysics · Physics 2009-12-31 David L. Wiltshire

We develop a cosmological theory in which the evolution of the universe is controlled by the cosmological constant and dominated by the associated vacuum energy. The universe starts as a classical de Sitter space with an infinite effective…

General Physics · Physics 2023-03-21 J. M. Greben

We present a model of the expanding Universe that begins in a zero energy vacuum state. The Universe results from the spontaneous breaking of the electroweak symmetry, wherein the vacuum with positive expectation energy produces the dark…

General Physics · Physics 2021-04-29 R. N. Henriksen

The bulk viscosity of cosmological fluid and the creation of cold dark matter both result in the generation of irreversible entropy (related to dissipative processes) in a homogeneous and isotropic universe. To consider such effects, the…

Cosmology and Nongalactic Astrophysics · Physics 2014-12-16 Nobuyoshi Komatsu , Shigeo Kimura

We show that dark matter with certain minimal properties can convert the majority of baryons in galaxies to black holes over hundred trillion year timescales. We argue that this has implications for cosmologies which propose that new…

High Energy Physics - Phenomenology · Physics 2024-08-23 Joseph Bramante , Nirmal Raj

The physical nature of the presently dominating enigmatic dark energy in the expanding universe is demonstrated to be explainable as an excess of the kinetic energy with respect to its potential energy. According to traditional Friedman…

Cosmology and Nongalactic Astrophysics · Physics 2018-03-14 Arved Sapar

The generalized second law of thermodynamics states that entropy always increases when all event horizons are attributed with an entropy proportional to their area. We test the generalized second law by investigating the change in entropy…

Astrophysics · Physics 2009-11-07 Tamara M. Davis , P. C. W. Davies , Charles H. Lineweaver

The present work shows that the second law of thermodynamics gets naturally satisfied during the entire cosmic evolution of the universe starting from inflation to the late dark energy era, without imposing any exotic condition. This makes…

General Relativity and Quantum Cosmology · Physics 2025-02-05 Sergei D. Odintsov , Tanmoy Paul , Soumitra SenGupta

Possible connections between quantum entanglement and cosmological eras are considered. In particular, assuming that two epochs are each other entangled, by measuring the entanglement degree, it is possible to recover dynamical properties…

General Relativity and Quantum Cosmology · Physics 2015-06-19 S. Capozziello , O. Luongo

We use the phase plane analysis technique of Madsen and Ellis to consider a universe with a true cosmological constant as well as a cosmological "constant" that is decaying. Time symmetric dynamics for the inflationary era allows eternally…

Cosmology and Nongalactic Astrophysics · Physics 2016-04-27 George F. R. Ellis , Emma Platts , David Sloan , Amanda Weltman

The existence of exact solutions which represent a lattice of black holes at a scalar-field-dominated cosmological bounce suggests that black holes could persist through successive eras of a cyclic cosmology. Here we explore some remarkable…

General Relativity and Quantum Cosmology · Physics 2017-04-11 Bernard Carr , Timothy Clifton , Alan Coley

If a macroscopic (random) classical system is put into a random state in phase space, it will of course the most likely have an almost maximal entropy according to second law of thermodynamics. We will show, however, the following theorem:…

High Energy Physics - Theory · Physics 2007-05-23 Holger B. Nielsen , Masao Ninomiya

After a discussion on several limiting cases where General Relativity turns into less sophisticated theories, we find that in the correct thermodynamical and cosmological weak field limit of Einstein's field equations the entropy of the…

General Physics · Physics 2010-12-14 Marcelo Samuel Berman

The consideration of dark energy's quanta, required also by thermodynamics, introduces its chemical potential into the cosmological equations. Isolating its main contribution, we obtain solutions with dark energy decaying to matter or…

Astrophysics · Physics 2007-05-23 J. Besprosvany

A six-dimensional universe with two branes in the "football-shaped" geometry leads to an almost realistic cosmology. We describe a family of exact solutions with time dependent characteristic size of internal space. After a short…

High Energy Physics - Theory · Physics 2010-04-05 Jan-Markus Schwindt , Christof Wetterich

Motivated by a recent work of one of us [1], we extend it by using quantum (or entropy) corrected new agegraphic dark energy in the Brans-Dicke cosmology. The correction terms are motivated from the loop quantum gravity which is one of the…

High Energy Physics - Theory · Physics 2011-01-04 Kayoomars Karami , Ahmad Sheykhi , Mubasher Jamil , Z. Azarmi , M. M. Soltanzadeh

The current observational data imply that the universe would end with a cosmic doomsday in the holographic dark energy model. However, unfortunately, the big-rip singularity will ruin the theoretical foundation of the holographic dark…

General Relativity and Quantum Cosmology · Physics 2010-04-30 Xin Zhang

In a homogeneous and isotropic universe bulk viscosity is the unique viscous effect capable to modify the background dynamics. Effects like shear viscosity or heat conduction can only change the evolution of the perturbations. The existence…

Cosmology and Nongalactic Astrophysics · Physics 2013-12-17 Hermano Velten , Jiaxin Wang , Xinhe Meng
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