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Related papers: Did the universe have a beginning?

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In this work, I have considered that the universe is filled with normal matter and phantom field (or tachyonic field). If the universe is filled with scalar field, Ellis et al have shown that emergent scenario is possible only for $k=+1$…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Ujjal Debnath

Intuitively, the totality of physical reality -- the Cosmos -- has a beginning only if (i) all parts of the Cosmos agree on the direction of time (the Direction Condition) and (ii) there is a boundary to the past of all non-initial…

History and Philosophy of Physics · Physics 2023-08-28 Daniel Linford

We propose a new approach to the model of an origin of the universe built by Oscar Klein and Hannes Alfv\'{e}n. Some modifications of assumptions underlying the model result in a possible scenario of the universe creation consistent with…

General Physics · Physics 2007-05-23 Andrzej Mercik , Szymon Mercik

The accelerated expansion of the universe is the most debatable cosmological scenario in the last two decades. Looking for the proper explanation of this scenario, researchers have presented a lot of proposals to discuss it. However,…

General Relativity and Quantum Cosmology · Physics 2023-01-11 Sanjay Mandal

The question of cosmic beginning has always attracted considerable attention from serious thinkers past and present. This article examines Ibn Sina's proposed solution to the vexed problem that given an eternally existing world and one…

History and Philosophy of Physics · Physics 2020-08-27 Syamsuddin Arif

Alternative scenarios to the Big Bang singularity have been subject of intense research for several decades by now. Most popular in this sense have been frameworks were such singularity is replaced by a bounce around some minimal…

General Relativity and Quantum Cosmology · Physics 2017-09-25 Emanuele Alesci , Gioele Botta , Francesco Cianfrani , Stefano Liberati

This paper outlines astrophysical issues related to the long term fate of the universe. We consider the evolution of planets, stars, stellar populations, galaxies, and the universe itself over time scales which greatly exceed the current…

Astrophysics · Physics 2008-11-26 Fred C. Adams , Gregory Laughlin

It is argued that human consciousness is likely to have emerged during the self-consistent evolution of the physical universe, through the gradual accumulation of biological entities' ability to tap into the intrinsic non-deterministic…

General Physics · Physics 2011-03-15 Xiaolei Zhang

We consider a non singular origin for the Universe starting from an Einstein static Universe, the so called "emergent universe" scenario, in the framework of a theory which uses two volume elements $\sqrt{-{g}}d^{4}x$ and $\Phi d^{4}x$,…

General Relativity and Quantum Cosmology · Physics 2015-05-27 E. I. Guendelman

As we follow our Universe to early times, we find that matter was crushed to high densities, somewhat similar to the behavior at a black hole singularity. String theory has made progress in explaining the internal structure of black holes,…

High Energy Physics - Theory · Physics 2008-12-18 Samir D. Mathur

Inter-universal entanglement may even exist in a multiverse in which there is no common space-time among the universes. In particular, the entanglement between the expanding and contracting branches of the universe might have observable…

General Relativity and Quantum Cosmology · Physics 2017-08-04 S. J. Robles-Pérez

In order to bypass the big bang singularity, we develop an emergent universe scenario within a covariant extension of General Relativity known as \emph{"Energy-Momentum Squared Gravity"}. The extra terms of the model emerge in the high…

General Relativity and Quantum Cosmology · Physics 2022-04-05 Mohsen Khodadi , Alireza Allahyari , Salvatore Capozziello

We consider the quantum creation of a universe with flat spatial sections and the topology of a 3-torus, taking into account the effect of Casimir energy. We show that the corresponding instantons are singular. Since these instantons…

General Relativity and Quantum Cosmology · Physics 2025-08-22 Alan H. Guth , Alexander Vilenkin

Recent developments in cosmology indicate that every history having a nonzero probability is realized in infinitely many distinct regions of spacetime. Thus, it appears that the universe contains infinitely many civilizations exactly like…

Physics and Society · Physics 2010-12-06 Joshua Knobe , Ken D. Olum , Alexander Vilenkin

In the no-boundary univers e the universe is created from an instanton. However, there does not exist any instanton for the ``realistic'' $FRW$ universe with a scalar field. The ``instanton'' leading to its quantum creation may be modified…

High Energy Physics - Theory · Physics 2007-05-23 Z. C. Wu

We consider a non singular origin for the Universe starting from an Einstein static Universe in the framework of a theory which uses two volume elements $\sqrt{-{g}}d^{4}x$ and $\Phi d^{4}x$, where $\Phi $ is a metric independent density,…

General Relativity and Quantum Cosmology · Physics 2015-05-28 E. I. Guendelman

The universe is certainly not yet in total thermodynamical equilibrium,so clearly some law telling about special initial conditions is needed. A universe or a system imposed to behave periodically gets thereby required ``initial…

High Energy Physics - Theory · Physics 2009-11-11 Holger B. Nielsen , Masao Ninomiya

A tradition handed down among physicists maintains that classical physics is a perfectly deterministic theory capable of predicting the future with absolute certainty, independently of any interpretations. It also tells that it was quantum…

History and Philosophy of Physics · Physics 2023-03-09 Flavio Del Santo

The transition from the quantum to the classical world is not yet understood. Here we take a new approach. Central to this is the understanding that measurement and actualization cannot occur except in some specific basis. But we have no…

Quantum Physics · Physics 2022-07-13 Stuart Kauffman , Sudip Patra

The possibility that the multiverse corresponds to physical reality deserves serious investigation. Having three different important theories,(quantum mechanics, string theory and inflation), predict the existence of the multiverse is…

General Relativity and Quantum Cosmology · Physics 2008-04-29 Laura Mersini-Houghton