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Related papers: Arrow(s) of Time without a Past Hypothesis

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The laws of Physics are time-reversible, making no qualitative distinction between the past and the future -- yet we can only go towards the future. This apparent contradiction is known as the "arrow of time problem". Its current resolution…

Discrete Mathematics · Computer Science 2024-08-23 Pablo Arrighi , Gilles Dowek , Amélia Durbec

Quantum gravity, the initial low entropy state of the Universe, and the problem of time are interlocking puzzles. In this article, we address the origin of the arrow of time from a cosmological perspective motivated by a novel approach to…

High Energy Physics - Theory · Physics 2015-06-04 Vishnu Jejjala , Michael Kavic , Djordje Minic , Chia-Hsiung Tze

Deutsch and Aguirre have recently shown that the solutions of certain dynamical systems typically contain a point of minimum size that they identify as an entropy minimum and from which the size and entropy increase to infinity in both…

General Relativity and Quantum Cosmology · Physics 2021-08-24 Julian Barbour

The puzzle of the thermodynamic arrow of time reduces to the question of how the universe could have had lower entropy in the past. I show that no special entropy lowering mechanism (or fluctuation) is necessary. As a consequence of…

Statistical Mechanics · Physics 2015-05-13 L. S. Schulman

Cosmic inflation claims to make the initial conditions of the standard big bang "generic". But Boltzmann taught us that the thermodynamic arrow of time arises from very non-generic ("low entropy") initial conditions. I discuss how to…

Astrophysics · Physics 2007-05-23 Andreas Albrecht

It is generally believed that a cosmological arrow of time must be associated with entropy production. Indeed, in his seminal work on cyclic cosmology, Tolman introduced a viscous fluid in order to make successive expansion/contraction…

General Relativity and Quantum Cosmology · Physics 2018-10-26 Varun Sahni , Yuri Shtanov , Aleksey Toporensky

In this paper we address the problem of the arrow of time from a cosmological point of view, rejecting the traditional entropic approach that defines the future direction of time as the direction of the entropy increase: from our…

Quantum Physics · Physics 2009-11-07 Mario Castagnino , Luis Lara , Olimpia Lombardi

We find ourselves in an extended era of entropy production. Unlike most other observations, the arrow of time is usually regarded as a constraint on initial conditions. I argue, however, that it primarily constrains the vacuum structure of…

High Energy Physics - Theory · Physics 2013-05-30 Raphael Bousso

Usually, it is supposed that irreversibility of time appears only in macrophysics. Here, we attempt to introduce the microphysical arrow of time assuming that at a fundamental level nature could be non-associative. Obtaining numerical…

General Physics · Physics 2022-11-02 Merab Gogberashvili

One of the most difficult problems in the foundations of physics is what gives rise to the arrow of time. Since the fundamental dynamical laws of physics are (essentially) symmetric in time, the explanation for time's arrow must come from…

History and Philosophy of Physics · Physics 2021-10-26 Eddy Keming Chen

Recently, Carroll and Chen [hep-th/0410270] suggested a promising natural explanation of the thermodynamic arrow of time. However, we criticize their assertion that there exists a Cauchy hypersurface with a minimal entropy and argue that…

High Energy Physics - Theory · Physics 2007-05-23 H. Nikolic

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

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 brought forward that viable theories of the physical world that have no variable at all that can play the role of time, do not exist; some notion of time is one of the very first ingredients a candidate theory should possess. Almost…

Quantum Physics · Physics 2018-04-05 Gerard t Hooft

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 present a novel solution to the low entropy and arrow of time puzzles of the initial state of the Universe. Our approach derives from the physics of a specific generalization of Matrix theory put forth in earlier work as the basis for a…

High Energy Physics - Theory · Physics 2010-05-25 Vishnu Jejjala , Michael Kavic , Djordje Minic , Chia-Hsiung Tze

It is shown that the structures in the universe can be interpreted to show a closed wheel of time, rather than a straight arrow. An analysis in $f(R)$ gravity model has been carried out to show that due to local observations a small arc at…

General Physics · Physics 2018-01-26 Bal Krishna Yadav , Murli Manohar Verma

This paper is a natural continuation of our previous paper arXiv:1011.4173 . We illustrated earlier that in classical Hamilton mechanics, for overwhelming majority of real chaotic macroscopic systems, alignment of their thermodynamic time…

General Physics · Physics 2013-07-15 Oleg Kupervasser

Based on the hypothesis that the (non-reversible) arrow of time is intrinsic in any system, no matter how small, the consequences are discussed. Within the framework of local quantum physics it is shown how such a semi-group action of time…

Mathematical Physics · Physics 2023-05-22 Detlev Buchholz , Klaus Fredenhagen

In this paper we have studied a generalized quantum theory and its consistent classical limit, which possess a well-defined arrow of time in their dynamics. The original quantum theory is defined as analytically dependent on complex time…

High Energy Physics - Theory · Physics 2007-05-23 V. V. Asadov , O. V. Kechkin
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