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Related papers: Time and irreversibility in an accelerating univer…

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An accelerated universe should naturally have a vacuum energy density determined by its dynamical curvature. The cosmological constant is most likely a temporary description of a dynamical variable that has been drastically evolving from…

General Relativity and Quantum Cosmology · Physics 2015-10-28 Joan Sola

In light of G\"{o}del's undecidability results (incomplete theorems) for math, quantum indeterminism indicates that physics and the Universe may be indeterministic, incomplete, and open in nature, and therefore demand no single unification…

General Physics · Physics 2020-03-11 Wanpeng Tan

In several previous papers we have argued for a global and non-entropic approach to the problem of the arrow of time, according to which the ''arrow'' is only a metaphorical way of expressing the geometrical time-asymmetry of the universe.…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Matias Aiello , Mario Castagnino , Olimpia Lombardi

A rather simple and non-technical exposition of our new approach to {\em Time, Quantum Physics, Black-Hole dynamics}, and {\em Cosmology}, based on non-critical string theory, is provided. A new fundamental principle, the {\em Procrustean…

High Energy Physics - Theory · Physics 2015-06-26 D. V. Nanopoulos

Starting from the revelation of the nature of inertial forces, this article discusses the subdivision of the basic physical concept of space-time and raises questions about the metric of standard cosmology. A new form of particle dynamics…

High Energy Physics - Theory · Physics 2024-06-25 ChiYi Chen

Combining intervals of ekpyrotic (ultra-slow) contraction with a (non-singular) classical bounce naturally leads to a novel cyclic theory of the universe in which the Hubble parameter, energy density and temperature oscillate periodically,…

General Relativity and Quantum Cosmology · Physics 2019-07-12 Anna Ijjas , Paul J. Steinhardt

We develop a new model for the Universe based on two key assumptions: first, the inertial energy of the Universe is a constant, and second, the total energy of a particle, the inertial plus the gravitational potential energy produced by the…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Hossein Shojaie , Mehrdad Farhoudi

We discuss how the classical notions of time and causal structure may emerge together with quantum-mechanical probabilities from a universal quantum state. For this, the process of decoherence between semiclassical branches is important.…

General Relativity and Quantum Cosmology · Physics 2025-06-24 Leonardo Chataignier , Claus Kiefer , Mritunjay Tyagi

Irreversibility is one of the most intriguing concepts in physics. While microscopic physical laws are perfectly reversible, macroscopic average behavior has a preferred direction of time. According to the second law of thermodynamics, this…

Quantum Physics · Physics 2017-04-12 T. B. Batalhao , A. M. Souza , R. S. Sarthour , I. S. Oliveira , M. Paternostro , E. Lutz , R. M. Serra

This article looks at how inhomogeneous spacetime models may be significant for cosmology. First it looks at how the averaging process may affect large scale dynamics, with backreaction effects leading to effective contributions to the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 George F R Ellis

The nature of time vis-a-vis relativity is critically examined. Based on the author's space-time interaction hypothesis of late 1970's, cosmological model with time-varying velocity of light is discussed.

General Relativity and Quantum Cosmology · Physics 2007-05-23 S. C. Tiwari

Astronomical observations have a unique ability to determine the laws of physics at distant times in the universe. They, therefore, have particular relevance in answering the basic question as to whether the laws of physics are invariant…

Cosmology and Nongalactic Astrophysics · Physics 2016-02-11 Rodger I. Thompson

A nonvanishing cosmological term in Einstein's equations implies a nonvanishing spacetime curvature even in absence of any kind of matter. It would, in consequence, affect many of the underlying kinematic tenets of physical theory. The…

General Relativity and Quantum Cosmology · Physics 2009-11-10 R. Aldrovandi , J. P. Beltran Almeida , J. G. Pereira

In the context of a parametric theory (with the time being a dynamical variable) we consider the coupling between the quantum vacuum and the background gravitation that pervades the universe (unavoidable because of the universality of…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Antonio F. Ranada , Alfredo Tiemblo

The gravitational force harbours a fundamental instability against collapse. In standard General Relativity without Quantum Mechanics, this implies the existence of black holes as natural, stable solutions of Einstein's equations. If one…

General Relativity and Quantum Cosmology · Physics 2017-08-23 Gerard 't Hooft

In an apparently unexplored region of relativistic spacetime, a simple thought experiment demonstrates that conjoined Lorentz transformations predict a proper clock at rest will run backwards and that prediction violates the logical…

Astrophysics · Physics 2007-05-23 Charles B. Leffert

Prigogine and Stengers (1988) have pointed to the centrality of the concepts of "time and eternity" for the cosmology contained in Newtonian physics, but they have not addressed this issue beyond the domain of physics. The construction of…

History and Philosophy of Physics · Physics 2010-03-16 Loet Leydesdorff

The picture of space-time that Minkowski created in 1907 has been followed by two important developments in physics not contained in the original picture: general relativity and quantum mechanics. We will argue that the use of concepts of…

General Relativity and Quantum Cosmology · Physics 2013-02-22 Rodolfo Gambini , Jorge Pullin

We argue that in classical and quantum theories of gravity the configuration space and Hilbert space may not be constructible through any finite procedure. If this is the case then the "problem of time" in quantum cosmology may be a…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Stuart Kauffman , Lee Smolin

The principles of General Relativity allow for a non-vanishing cosmological constant, which can possibly be interpreted at least partially in terms of quantum-fluctuations of matter fields. Depending on sign and magnitude it can cause…

Astrophysics · Physics 2007-05-23 Domenico Giulini , Norbert Straumann