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Related papers: How and Why the Universe Began

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We study some claims in Krauss' recent book, \emph{A Universe from Nothing: Why there is something rather than nothing}, that are employed to show that a universe can come from "nothing". In this brief paper, we show that many of the claims…

General Physics · Physics 2016-03-22 Ikjyot Singh Kohli

An introduction to modern theories for the origin of structure in the Universe is given. After a brief review of the growth of cosmological perturbations in an expanding Universe and a summary of some important observational results, the…

Astrophysics · Physics 2008-02-03 Robert H. Brandenberger

An approach to modelling the universe based on the requisites of gravitational energy. This model is explained as it relates to the stages of the universal life cycle and the continued existence of the universe as it is known today. The…

Astrophysics · Physics 2007-05-23 Anthony Baldocchi

In this note, it is shown that nonvanishing spatial curvature produces primordial matter in the initially empty universe due to quantum gravity effects. This matter decays faster than radiation and is described by a stiff equation of state.…

General Relativity and Quantum Cosmology · Physics 2026-04-14 V. E. Kuzmichev , V. V. Kuzmichev

Two fundamental laws are needed for prediction in the universe: (1) a basic dynamical law and (2) a law for the cosmological initial condition. Quantum cosmology is the area of basic research concerned with the search for a theory of the…

General Relativity and Quantum Cosmology · Physics 2008-02-03 James B. Hartle

An interesting idea is that the universe could be spontaneously created from nothing, but no rigorous proof has been given. In this paper, we present such a proof based on the analytic solutions of the Wheeler-DeWitt equation (WDWE).…

General Relativity and Quantum Cosmology · Physics 2014-04-07 Dongshan He , Dongfeng Gao , Qing-yu Cai

We show that if Dark Matter is made up of light bosons, they form a Bose-Einstein condensate in the early Universe. This in turn naturally induces a Dark Energy of approximately equal density and exerting negative pressure.This explains the…

General Relativity and Quantum Cosmology · Physics 2021-02-03 Saurya Das

We find a class of solutions for a homogeneous and isotropic universe in which the initially expanding universe stops expanding, experiences contraction, and then expands again (the "bounce"), in the framework of Einstein gravity with a…

General Relativity and Quantum Cosmology · Physics 2019-06-26 Hiroki Matsui , Fuminobu Takahashi , Takahiro Terada

Here, creation of the universe is obtained only from gravity sector. The dynamical universe begins with two basic ingredients (i) vacuum energy, also called dark energy (as vacuum energy is not observed) and (ii) background radiation. These…

High Energy Physics - Theory · Physics 2007-05-23 S. K. Srivastava

Within the framework of an eternal inflationary scenario, a natural question regarding the production of eternal bubbles is the essential condition requires to have a universe capable of generating life. In either an open or a closed…

Cosmology and Nongalactic Astrophysics · Physics 2017-08-30 Sohrab Rahvar

We describe the very nature of the elementary particles, which our (visible) Universe consists of. We point out that they are not point-like, and we depict their ways of interacting. We also address puzzles that occur even in the absence of…

Popular Physics · Physics 2021-01-27 Wolfgang Bietenholz

The existence of light (a massless U(1) gauge boson) is one of unresolved mysteries in nature. In this paper, we would like to propose that light is originated from certain quantum orders in our vacuum. We will construct quantum models on…

High Energy Physics - Theory · Physics 2009-11-07 Xiao-Gang Wen

The exactly solvable quantum model of the homogeneous, isotropic and closed universe in the matter-energy production epoch is considered. It is assumed that the universe is originally filled with a uniform scalar field and a perfect fluid…

General Relativity and Quantum Cosmology · Physics 2011-07-19 V. E. Kuzmichev , V. V. Kuzmichev

The present-day Universe appears to be homogeneous on very large scales. Yet when the casual structure of the early Universe is considered, it becomes apparent that the early Universe must have been highly inhomogeneous. The current…

General Relativity and Quantum Cosmology · Physics 2011-03-04 Krzysztof Bolejko , William R. Stoeger

In the Friedmann equations, an infinite initial density is avoided only when the universe is spatially flat. With such equations being then valid when the scale factor $a=0$, the universe must also be in the state of vacuum when $a$ is…

General Relativity and Quantum Cosmology · Physics 2013-06-26 N. Tsitverblit

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

The Universe contains everything that exists, including life. And all that exists, including life, obeys universal physical laws. Do those laws then give adequate foundations for a complete explanation of biological phenomena? We discuss…

History and Philosophy of Physics · Physics 2022-04-29 Marina Cortês , Stuart A. Kauffman , Andrew R. Liddle , Lee Smolin

The idea that a background of invisible material pervades the whole universe is as old as the history of natural philosophy. Modern particle physics and cosmology support that idea and identify in the cosmic vacuum the ultimate source of…

High Energy Physics - Phenomenology · Physics 2007-05-23 A. Aurilia , E. Spallucci

We advance a famous principle - causality principle - but under a new view. This principle is a principium automatically leading to most fundamental laws of the nature. It is the inner origin of variation, rules evolutionary processes of…

General Physics · Physics 2007-05-23 Do Minh Chi

In the inflationary scenario all the matter constituting the universe was created from the process of reheating after inflation. Recent development of the theory of reheating is briefly reviewed. The list of topics includes elementary…

Astrophysics · Physics 2007-05-23 Lev Kofman
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