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This paper studies whether the generalized second law of thermodynamics is fulfilled in the transition from a generic initial Einstein static phase to the inflationary phase, with constant Hubble rate, and from the end of the latter to the…

General Relativity and Quantum Cosmology · Physics 2015-06-03 Sergio del Campo , Ramon Herrera , Diego Pavon

In the scientific and engineering literature, the second law of thermodynamics is expressed in terms of the behavior of entropy in reversible and irreversible processes. According to the prevailing statistical mechanics interpretation the…

Quantum Physics · Physics 2007-05-23 Elias P. Gyftopoulos , Gian Paolo Beretta

Friedmann-Lemaitre equations with contributions coming from matter, curvature, cosmological constant, and radiation, when written in terms of conformal time u rather than in terms of cosmic time t, can be solved explicitly in terms of…

General Relativity and Quantum Cosmology · Physics 2018-09-12 Robert Coquereaux

A wave model for the interconversion of photon particle behavior and wave phenomena is examined in relation to the adiabatic spatial expansion of the Universe. An historical perspective of the mathematics of physical science over the 20th…

General Physics · Physics 2009-06-23 Paul E. Field

We consider the evolution of a flat Friedmann-Robertson-Walker Universe, filled with a causal bulk viscous cosmological fluid, in the presence of variable gravitational and cosmological constants. The basic equation for the Hubble…

General Relativity and Quantum Cosmology · Physics 2008-11-26 M. K. Mak , J. A. Belinchon , T. Harko

Recent astronomical observations of distant supernovae light-curves suggest that the expansion of the universe has recently begun to accelerate. Acceleration is created by an anti-gravitational repulsive stress, like that produced by a…

Astrophysics · Physics 2009-10-31 John Barrow , Rachel Bean , Joao Magueijo

A universal theory of chaos is presented which postulates the self-organized ordered growth of self-similar, scale invariant, eddy energy structures by space-time integration of inherent microscale energy generation mechanisms in the medium…

chao-dyn · Physics 2007-05-23 Mary Selvam Amujuri

The equations of fluid motions are considered in the case of internal energy depending on mass density, volume entropy and their spatial derivatives. The model corresponds to domains with large density gradients in which the temperature is…

Fluid Dynamics · Physics 2017-06-27 Henri Gouin

This paper presents an information-theoretic view of how an observer within a quantum system will perceive his world. It is argued that because of the indistinguishability of quantum particles, a coherent state will appear to an observer…

Astrophysics · Physics 2007-05-23 Subhash Kak

The general theory of relativity is the most popular theory to describe the dynamics of a system (especially the Universe) under gravity. In this framework, the solution of the Einstein field equation under curved space-time yields the…

General Relativity and Quantum Cosmology · Physics 2024-02-06 Subhayan Maity , Manojit Das

The first part of this paper is a condensed synthesis of the matter presented in several previous ones. It begins with an argumentation showing that the first and second laws of thermodynamics are incompatible with one another if they are…

General Physics · Physics 2010-02-21 Jean-Louis Tane

The physics of the expansion of the universe is still a poorly studied subject of the standard cosmological model. This because the concept of expanding space can not be tested in the laboratory and because ``expansion'' means continuous…

Astrophysics · Physics 2009-11-13 Yurij Baryshev

We consider a (1+1) dimensional scalar field theory that supports oscillons, which are localized, oscillatory, stable solutions to nonlinear equations of motion. We study this theory in an expanding background and show that oscillons now…

High Energy Physics - Theory · Physics 2008-11-26 E. Farhi , N. Graham , A. H. Guth , N. Iqbal , R. R. Rosales , N. Stamatopoulos

In this paper we describe the evolution of the Universe in terms of the Friedmann equation, which takes into account of the composition and geometry of the Universe. The dependence of the solution on the geometry and composition for…

Popular Physics · Physics 2020-11-02 Vinicius S. Aderaldo , Victor P. Goncalves

Using information theory we derive a thermodynamics for systems evolving under a collective motion, i.e. under a time-odd constraint. An illustration within the Lattice gas Model is given for two model cases: a collision between two complex…

Nuclear Theory · Physics 2015-06-26 F. Gulminelli , PH. Chomaz

Constancy of the speed of light together with the Hubble law lead in a doctrine of expanding universe to a conclusion that universe evolution is not only an expansion of space but also a deceleration of the course of physical time (Taganov,…

General Physics · Physics 2008-07-28 Igor N. Taganov

Why in our Universe the laws of thermodynamics are valid? In the paper is demonstrated the reason of it: if the time and the space are multifractal and the Universe is in an equilibrium state the laws of the thermodynamics are consequences…

General Physics · Physics 2007-05-23 L. Ya. Kobelev

We prove the conservation of energy for weak and statistical solutions of the two-dimensional Euler equations, generated as strong (in an appropriate topology) limits of the underlying Navier-Stokes equations and a Monte Carlo-Spectral…

Analysis of PDEs · Mathematics 2021-02-25 S. Lanthaler , S. Mishra , C. Parés-Pulido

In the late 1990s, observations of type Ia supernovae led to the astounding discovery that the universe is expanding at an accelerating rate. The explanation of this anomalous acceleration has been one of the great problems in physics since…

General Physics · Physics 2015-11-09 Wun-Yi Shu

The Hamiltonian defines the dynamical properties of the universe. Evidence from particle physics shows that there is a different version of the Hamiltonian for each direction of time. As there is no physical basis for the universe to be…

Quantum Physics · Physics 2017-07-14 Joan A. Vaccaro