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Related papers: The Time-Asymmetry and the Entropy Gap

200 papers

An asymmetry exists between time and space in the sense that physical systems inevitably evolve over time whereas there is no corresponding ubiquitous translation over space. The asymmetry, which is presumed to be elemental, is represented…

Quantum Physics · Physics 2016-01-25 Joan A. Vaccaro

A new definition of entropy is introduced using a model that simulates an expanding space-time compatible with the fundamental principle of cosmology. The entropy is obtained by mean of a state function that measures the variation of the…

General Physics · Physics 2024-05-01 Faycal Ben Adda

We investigate possible astronomical manifestations of space-time anisotropy. The homogeneous vacuum Kasner solution was chosen as a reference anisotropic cosmological model because there are no effects caused by inhomogeneity in this…

General Relativity and Quantum Cosmology · Physics 2023-05-30 S L Parnovsky

In previous work, we showed that the answer to the question posed in the title cannot be found within an equilibrium setting. The inclusion of {\em dynamical} backreaction effects from massive long wavelength modes on the initial DeSitter…

High Energy Physics - Theory · Physics 2007-05-23 R. Holman , L. Mersini-Houghton

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

Model independent arguments following from the Covariant Entropy Principle imply that causal diamonds in the very early universe were entirely filled with a single equilibrated system with finite entropy. A universe where this condition…

High Energy Physics - Theory · Physics 2021-09-14 Tom Banks , Willy Fischler

We propose an interpretation of the expansion and acceleration of the Universe from an information theoretic viewpoint. We obtain the time evolution of the configuration entropy of the mass distribution in a static Universe and show that…

General Relativity and Quantum Cosmology · Physics 2017-08-16 Biswajit Pandey

If an asymmetry in time does not arise from the fundamental dynamical laws of physics, it may be found in special boundary conditions. The argument normally goes that since thermodynamic entropy in the past is lower than in the future…

Quantum Physics · Physics 2024-07-23 Jim Al-Khalili , Eddy Keming Chen

It is argued that a fundamental time asymmetry could arise from the global structure of the space manifold. The proposed mechanism relies on the CPT anomaly of certain chiral gauge theories defined over a multiply connected space manifold.…

General Relativity and Quantum Cosmology · Physics 2009-11-07 F. R. Klinkhamer

Curiously, our Universe was born in a low entropy state, with abundant free energy to power stars and life. The form that this free energy takes is usually thought to be gravitational: the Universe is almost perfectly smooth, and so can…

Cosmology and Nongalactic Astrophysics · Physics 2023-06-22 Luke A. Barnes , Geraint F. Lewis

Understanding the evolution of entropy in the universe is a fundamental aspect of cosmology. This paper investigates the evolution of entropy in a spatially flat $K=0$ universe, focusing on the contributions of matter, radiation, and dark…

General Relativity and Quantum Cosmology · Physics 2025-07-16 Tanisha Joshi , S. D Pathak

A global definition of time-asymmetry is presented. Schulman's two arrows of time model is criticized.

General Relativity and Quantum Cosmology · Physics 2007-05-23 Mario Castagnino , Luis Lara , Olimpia Lombardi

Time is a parameter playing a central role in our most fundamental modelling of natural laws. Relativity theory shows that the comparison of times measured by different clocks depends on their relative motion and on the strength of the…

General Relativity and Quantum Cosmology · Physics 2017-07-25 Hauret Clementine , Magain Pierre , Biernaux Judith

We assume that the universe consists of clusters which in turns have sub-clusters and the sub-clusters have sub-subclusters and so on. Confining to three-dimensional space, it is shown that the universe is expanding if entropy of the…

General Physics · Physics 2007-05-23 Shahid N. Afridi , M. Khalid Khan

Based on Newton's laws reformulated in the Hamiltonian dynamics combined with statistical mechanics, we formulate a statistical mechanical theory supporting the hypothesis of a closed oscillating universe. We find that the behaviour of the…

Statistical Mechanics · Physics 2015-05-13 A. Perez-Madrid , I. Santamaria-Holek

Bousso's entropy bound is a conjecture that the entropy through a null hypersurface emanating from a two-dimensional surface with a nonpositive expansion is bounded by the area of that two-dimensional surface. We investigate the validity of…

General Relativity and Quantum Cosmology · Physics 2023-03-31 Takamasa Kanai , Kimihiro Nomura , Daisuke Yoshida

In this work I show by a first principles calculation that quantum states describing massive relativistic free spinning particles obey kinematical conditions whose origin can be traced to parity as a good quantum number. These conditions…

High Energy Physics - Phenomenology · Physics 2022-12-05 Mauro Napsuciale

There is a paradox in the standard model of cosmology. How can matter in the early universe have been in thermal equilibrium, indicating maximum entropy, but the initial state also have been low entropy (the "past hypothesis"), so as to…

General Relativity and Quantum Cosmology · Physics 2023-12-21 Jordan Scharnhorst , Anthony Aguirre

It is explained how the unification of resonance and decay phenomena into a consistent mathematical theory leads to quantum mechanical time-asymmetry. This provides the theoretical basis for a subsequent paper II in which the interpretation…

Quantum Physics · Physics 2007-05-23 A. Bohm , H. Kaldass , S. Komy

Nature's many complex systems--physical, biological, and cultural--are islands of low-entropy order within increasingly disordered seas of surrounding, high-entropy chaos. Energy is a principal facilitator of the rising complexity of all…

Popular Physics · Physics 2015-12-17 Eric J. Chaisson