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Related papers: Entropy, Black holes, and the New Cyclic Universe

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In cyclic universe models based on a single scalar field (e.g., the radion determining the distance between branes in M-theory), virtually the entire universe makes it through the ekpyrotic smoothing and flattening phase, bounces, and…

High Energy Physics - Theory · Physics 2009-11-13 Jean-Luc Lehners , Paul J. Steinhardt

In this talk, we discuss the possibility that the vacuum is dynamically determined in the history of the universe. The point is that some of the bubbles with a certain vacuum shrink by the evolution of the universe via gravity and may…

Astrophysics · Physics 2009-10-31 Nobuhiro Maekawa

Typically, the entropy of an isolated system in equilibrium is calculated by counting the number of accessible microstates, or in more general cases by using the Gibbs formula. In irreversible processes entropy spontaneously increases and…

Statistical Mechanics · Physics 2020-04-16 Taha A Malik , Rafael Lopez-Mobilia

Ekpyrotic and cyclic cosmologies provide theories of the very early and of the very late universe. In these models, the big bang is described as a collision of branes - and thus the big bang is not the beginning of time. Before the big…

Astrophysics · Physics 2011-03-10 Jean-Luc Lehners

We extend mass scale sequence to a mass tree. From mass tree, the evolution of the universe is described by three stages: chaos, inflation and expansion. The first two stages have c mutations and the inflation appears as a step by step…

General Physics · Physics 2020-05-06 Wuliang Huang , Xiaodong Huang

Dynamical solutions for an evolving multiple network of black holes near a cosmological bounce dominated by a scalar field are investigated. In particular, we consider the class of black hole lattice models in a hyperspherical cosmology,…

General Relativity and Quantum Cosmology · Physics 2021-01-06 A. A. Coley

The evaporation of the black holes during the very early universe is studied. Starting from black hole filled universe, the distiributions of particle species are calculated and showed, that they differ remarkably from the corresponding…

High Energy Physics - Phenomenology · Physics 2009-10-31 I. Vilja

We present a novel model-independent generic mechanism for primordial black hole formation within the context of non-singular matter bouncing cosmology. In particular, considering a short duration transition from the matter contracting…

General Relativity and Quantum Cosmology · Physics 2024-06-21 Theodoros Papanikolaou , Shreya Banerjee , Yi-Fu Cai , Salvatore Capozziello , Emmanuel N. Saridakis

We discuss the evolution of the universe in the context of the second law of thermodynamics from its early stages to the far future. Cosmological observations suggest that most matter and radiation will be absorbed by the cosmological…

General Relativity and Quantum Cosmology · Physics 2013-04-03 Andrew P. Lundgren , Ruxandra Bondarescu , Mihai Bondarescu

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

In a recent work we have argued that nosy energy momentum diffusion due to space-time discreteness at the Planck scale (naturally expected to arise from quantum gravity) can be responsible for the generation of a cosmological constant…

General Relativity and Quantum Cosmology · Physics 2019-11-15 Alejandro Perez , Daniel Sudarsky

A simple model of a universe is presented composed of black holes and black branes. It uses the most simplest approximations and models of General Relativity and Quantum Dynamics to offer an idea of an unification and gives a possible…

Astrophysics · Physics 2007-05-23 H. Genreith

While the basic laws of physics seem time-reversal invariant, our understanding of the apparent irreversibility of the macroscopic world is well grounded in the notion of entropy. Because astrophysics deals with the largest structures in…

General Physics · Physics 2015-07-30 David Garofalo

In this paper we investigate a steady accretion within the Einstein-Straus vacuole, in the presence of the cosmological constant. The dark energy damps the mass accretion rate and --- above certain limit --- completely stops the steady…

General Relativity and Quantum Cosmology · Physics 2015-06-12 Janusz Karkowski , Edward Malec

We discuss the evolution of radiation and Bekenstein-Hawking entropies in expanding isotropic universes. We establish a general relation which shows why it is inevitable that there is currently a huge difference in the numerical values of…

Astrophysics · Physics 2009-10-31 John D. Barrow

We address the question of universes inside a $\Lambda$ black hole which is described by a spherically symmetric globally regular solution to the Einstein equations with a variable cosmological term $\Lambda_{\mu\nu}$, asymptotically…

General Relativity and Quantum Cosmology · Physics 2009-11-07 I. G. Dymnikova , A. Dobosz , M. L. Fil'chenkov , A. Gromov

The black hole information paradox forces us into a strange situation: we must find a way to break the semiclassical approximation in a domain where no quantum gravity effects would normally be expected. Traditional quantizations of gravity…

High Energy Physics - Theory · Physics 2015-06-05 Samir D. Mathur

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

Recollapsing homogeneous and isotropic models present one of the key ingredients for cyclic scenarios. This is considered here within a quantum cosmological framework in presence of a free scalar field with, in turn, a negative cosmological…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Martin Bojowald , Reza Tavakol

Although nonsingular spacetimes and those containing black holes are qualitatively quite different, there are continuous families of configurations that connect the two. In this paper we use self-gravitating monopole solutions as tools for…

High Energy Physics - Theory · Physics 2009-10-31 Arthur Lue , Erick J. Weinberg