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A single mechanism, endemic to the standard model of physics, is proposed to explain wavefunction collapse, classical motion, dissipation, equilibration, and the transition from pure quantum mechanics through open system decoherence to the…

General Physics · Physics 2024-09-23 J. H. Brownell

We analyze a category of problems that is of interest in many physical situations, including those encountered in introductory physics classes: systems with two well-delineated parts that exchange energy, eventually reaching a shared…

Classical Physics · Physics 2019-10-31 Jonathan Bougie , Asim Gangopadhyaya

Hamiltonian mechanics describes the evolution of a system through its Hamiltonian. The Hamiltonian typically also represents the energy observable, a Noether-conserved quantity associated with the time-invariance of the law of evolution. In…

Quantum Physics · Physics 2024-03-29 Libo Jiang , Daniel R. Terno , Oscar Dahlsten

We show that the equations which describe irreversible evolution of a system can be derived from a variational principle. We suggest a Lagrangian, which depends on the properties of the normal and the so-called "mirror-image" system. The…

Statistical Mechanics · Physics 2015-02-10 K. S. Glavatskiy

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 the conjecture that rather than the second law of thermodynamics inevitably be breached as matter approaches a big crunch or a black hole singularity, the order of events should reverse, a model of the universe that resolves a…

General Physics · Physics 2007-05-23 Peter Lynds

We derive a unified expansion law for our universe from the first law of thermodynamics on the apparent horizon, where entropic evolution depicts the emergence of cosmic space. The derivation advances a general form for degrees of freedom…

General Relativity and Quantum Cosmology · Physics 2023-02-22 Hassan Basari V. T. , P. B. Krishna , Titus K. Mathew

My goal is to study the dynamics of the Universe from a relational perspective based on the happening of events in temporal relation to each other and their respective points of reference. Accordingly, the flow of time was modeled as the…

General Physics · Physics 2025-05-13 Bruce M Boman

Active motion is a concept in complex systems theory and was successfully applied to various problems in nonlinear dynamics. Explicit studies for gravitational potentials were missing so far. We interpret the Friedmann equations with…

High Energy Physics - Theory · Physics 2011-08-11 Alexander Gluck , Helmuth Huffel , Sasa Ilijic , Gerald Kelnhofer

We develop a thermal description for photon modes within the context of bouncing universe. Within this study, we start with a Lorentz-breaking dispersion relation which accounts for modified Friedmann equations with a bounce solution. We…

High Energy Physics - Theory · Physics 2022-01-27 A. A. Araújo Filho , A. Yu. Petrov

Exact solutions for a model with variable $G$, $\Lambda$ and bulk viscosity are obtained. Inflationary solutions with constant (de Sitter-type) and variable energy density are found. An expanding anisotropic universe is found to isotropize…

General Relativity and Quantum Cosmology · Physics 2014-11-17 Arbab I. Arbab

We use the dynamics of a galaxy, set up initially at a constant proper distance from an observer, to derive and illustrate two counter-intuitive general relativistic results. Although the galaxy does gradually join the expansion of the…

Astrophysics · Physics 2014-10-13 Tamara M. Davis , Charles H. Lineweaver , John K. Webb

This paper discusses an ordinary homogeneous differential equation of the second order with constant real-valued coefficients. The solution of this equation has to satisfy additional conditions. The first of the conditions stems from the…

General Physics · Physics 2007-05-23 Felix A. Hovsepian

The discovery that the expansion of the universe is accelerating in time is a major discovery which still awaits adequate explanation. It is generally agreed that this implies a cosmic repulsion as a result of the existence of a…

General Physics · Physics 2008-11-26 R. F. O'Connell

Assuming a cellular structure for the space-time, we propose a model in which the expansion of the universe is understood as a decrumpling process, much like the one we know from polymeric surfaces. The dimension of space is then a…

General Relativity and Quantum Cosmology · Physics 2007-05-23 M. Khorrami , M. Mansouri , M. Mohazzab

All the relativistic cosmological models of the universe, except Einstein's static model, imply that the 3-space of the spacetime of the universe is also expanding apart from the matter and the radiation in it. However, there is no…

General Physics · Physics 2009-01-15 R. K. Thakur

The developed theory proves that a universal vortex motion, along with the pressure variation in a space continuum called ether, is actually the source of the universal gravitation and creation of celestial bodies and their motion in the…

Astrophysics · Physics 2007-05-23 S. A. Orlov

The cosmological constant (lambda) of general relativity is a natural consequence of embedding Einstein's theory in a five-dimensional theory of the type needed for unification. The exact 5D solution for lambda less than 0 shows waves in…

General Relativity and Quantum Cosmology · Physics 2014-11-04 Paul S. Wesson

In this work, we review the results of Refs [1]-[5] dedicated to the description of the early Universe cosmology induced by quantum and thermal effects in superstring theories. The present evolution of the Universe is described very…

High Energy Physics - Theory · Physics 2021-01-05 F. Bourliot , J. Estes , C. Kounnas , H. Partouche

The general relativistic cosmological Friedmann equations which describe how the scale factor of the universe evolves are expanded explicitly to include energy forms not usually seen. The evolution of the universe as predicted by the…

Astrophysics · Physics 2008-11-26 Robert J. Nemiroff , Bijunath Patla
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