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Related papers: The Time-Asymmetry and the Entropy Gap

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The universe is certainly not yet in total thermodynamical equilibrium,so clearly some law telling about special initial conditions is needed. A universe or a system imposed to behave periodically gets thereby required ``initial…

High Energy Physics - Theory · Physics 2009-11-11 Holger B. Nielsen , Masao Ninomiya

The entropy of the observable universe is increasing. Thus, at earlier times the entropy was lower. However, the cosmic microwave background radiation reveals an apparently high entropy universe close to thermal and chemical equilibrium. A…

General Relativity and Quantum Cosmology · Physics 2017-10-11 Vihan M. Patel , and Charles H. Lineweaver

The universal validity of the second law of thermodynamics is widely attributed to a finely tuned initial condition of the universe. This creates a problem: why is the universe atypical? We suggest that the problem is an artefact created by…

General Relativity and Quantum Cosmology · Physics 2015-07-27 Julian Barbour , Tim Koslowski , Flavio Mercati

The study considers advantages of the introduced measure of time based on the entropy change under irreversible processes (entropy production). Using the example of non-equilibrium expansion of an ideal gas in vacuum, such a measure is…

Statistical Mechanics · Physics 2016-08-24 Leonid M. Martyushev , Evgenii V. Shaiapin

The second law of thermodynamics is asymmetric with respect to time as it says that the entropy of the universe must have been lower in the past and will be higher in the future. How this time-asymmetric law arises from the time-symmetric…

Statistical Mechanics · Physics 2021-06-07 Sivapalan Chelvaniththilan

It is widely accepted that temporal asymmetry is largely a cosmological problem; the task of explaining temporal asymmetry reduces in the main to that of explaining an aspect of the condition of the early universe. However, cosmologists who…

General Relativity and Quantum Cosmology · Physics 2009-09-25 Huw Price

According to statistical mechanics, micro-states of an isolated physical system (say, a gas in a box) at time $t_0$ in a given macro-state of less-than-maximal entropy typically evolve in such a way that the entropy at time $t$ increases…

Cosmology and Nongalactic Astrophysics · Physics 2016-07-27 Sheldon Goldstein , Roderich Tumulka , Nino Zanghi

We note that the observable part of universe at a certain time t_P is necessarily limited, when there is a beginning of universe. We argue that an appropriate spacetime region associated with an observer from tI to t_P is the causal diamond…

General Relativity and Quantum Cosmology · Physics 2015-06-12 Dongsu Bak

We discuss the entropy generation in quantum tunneling of a relativistic particle under the influence of a time varying force with the help of squeezing formalism. It is shown that if one associates classical coarse grained entropy to the…

General Relativity and Quantum Cosmology · Physics 2008-02-03 A. Feinstein , M. A. Pérez Sebastián

Two major apparently unrelated problems, that of the origin of time in the universe associated with quantum gravity and to the entropy in de Sitter cosmological models, are found to have their origin in a single physical phenomenon: the…

General Relativity and Quantum Cosmology · Physics 2011-04-15 Gerald Horwitz

A very simplified model of the Universe is considered in order to propose an alternative approach to the irreversible evolution of the Universe at very early times. The entropy generation at the quantum stage can be thought as a consequence…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Mario A. Castagnino , Fabian H. Gaioli , Daniel M. Sforza

In the multiverse, the universes can be created in entangled pairs with spacetimes that are both expanding in terms of the time variables experienced by internal observers in their particle physics experiments. The time variables of the two…

General Relativity and Quantum Cosmology · Physics 2017-06-21 Salvador J. Robles-Perez

It is demonstrated how a convenient choice of the mathematical structure of the quantum cosmology superspace, precisely the definition of a convenient regular state superspace and the restriction of the dynamics to this space, yields…

General Relativity and Quantum Cosmology · Physics 2010-11-19 Mario Castagnino

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

The emergence of a direction of time in statistical mechanics from an underlying time-reversal-invariant dynamics is explained by examining a simple model. The manner in which time-reversal symmetry is preserved and the role of initial…

Statistical Mechanics · Physics 2009-10-31 Vinay Ambegaokar , Aashish Clerk

A possible mechanism of time is formulated by developing an idea of time replaced by quantum correlations, with the aid of modern quantum information theory. We invent a microscopic model, where correlations of a closed system are steadily…

Quantum Physics · Physics 2011-11-14 Akimasa Miyake

Cosmological adiabatic particle creation results in the generation of irreversible entropy. The evolution of this entropy is examined in a flat Friedmann--Robertson--Walker universe at late times, using a dissipative model with a power-law…

General Relativity and Quantum Cosmology · Physics 2020-09-16 Nobuyoshi Komatsu

According to the second law of thermodynamics, the arrow of time points to an ever increasing entropy of the Universe. However, exactly how the entropy evolves with time and what drives the growth remain largely unknown. Here, for the first…

Cosmology and Nongalactic Astrophysics · Physics 2012-11-09 Xinghai Zhao , Yuexing Li , Qirong Zhu , Derek Fox

Based on an extended time-space symmetry, a cylindrical model of gravitational geometrical dynamics with two time-like extra-dimensions leads to a microscopic geodesic description of the curved space-time. Due to interaction of a Higgs-like…

General Physics · Physics 2015-10-15 Vo Van Thuan

A Universe filled with a homogeneous scalar field exhibits `Cosmological hysteresis'. Cosmological hysteresis is caused by the asymmetry in the equation of state during expansion and contraction. This asymmetry results in the formation of a…

General Relativity and Quantum Cosmology · Physics 2013-05-30 Varun Sahni , Aleksey Toporensky
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