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Related papers: A New Perspective to Cosmic Evolution and Vacuum S…

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The cosmological constant problem is examined under the assumption that the extrinsic curvature of the space-time contributes to the vacuum. A compensation mechanism based on a variable cosmological term is proposed. Under a suitable…

General Relativity and Quantum Cosmology · Physics 2009-09-25 M. D. Maia , G. S. Silva

Universe structure emerges in the unreduced, complex-dynamical interaction process with the simplest initial configuration (two attracting homogeneous fields). The unreduced interaction analysis avoiding any perturbative model gives…

General Physics · Physics 2015-03-20 Andrei P. Kirilyuk

Quantum theory, general relativity, the standard model of particle physics, and the $\Lambda$CDM model of cosmology have all been spectacularly successful within their respective regimes of applicability, but many central problems remain…

General Physics · Physics 2026-05-26 Roland E. Allen

We examine in a cosmological context the conditions for unbroken supersymmetry in N=1 supergravity in D=10 dimensions. We show that the cosmological solutions of the equations of motion obtained considering only the bosonic sector…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Stefano Foffa , Michele Maggiore , Riccardo Sturani

Self-similar, spherically symmetric cosmological models with a perfect fluid and a scalar field with an exponential potential are investigated. New variables are defined which lead to a compact state space, and dynamical systems methods are…

General Relativity and Quantum Cosmology · Physics 2010-11-19 Alan Coley , Martin Goliath

We propose that the Universe created from "nothing" with relatively small particles number and quickly relaxed to quasiequilibrium state at the Planck parameters. The classic cosmological solution for this Universe with Lambda-term has two…

General Relativity and Quantum Cosmology · Physics 2009-12-30 V. Burdyuzha , O. Lalakulich , Yu. Ponomarev , G. Vereshkov

Over the past three years we have determined the basic features of the Universe -- spatially flat; accelerating; comprised of 1/3 a new form of matter, 2/3 a new form of energy, with some ordinary matter and a dash of massive neutrinos; and…

Astrophysics · Physics 2009-11-07 Michael S. Turner

The production of gravitational vacuum defects and their contribution in energy density of the Universe are discussed. These topological microstructures could be produced as the result of defect creation of the Universe from "nothing" as…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Vladimir Burdyuzha , J. A. de Freitas Pacheco , Grigory Vereshkov

This paper investigates the phenomenon of emergence of spatial curvature. This phenomenon is absent in the Standard Cosmological Model, which has a flat and fixed spatial curvature (small perturbations are considered in the Standard…

Cosmology and Nongalactic Astrophysics · Physics 2017-09-01 Krzysztof Bolejko

In a unified picture both inflation and present dynamical dark energy arise from the same scalar field. The history of the Universe describes a crossover from a scale invariant "past fixed point" where all particles are massless, to a…

High Energy Physics - Theory · Physics 2015-12-09 C. Wetterich

We study the cosmological evolution of a type-0 string theory by employing non-criticality, which may be induced by fluctuations of the D3 brane worlds. We check the consistency of the approach to O(alpha ') in the corresponding…

High Energy Physics - Theory · Physics 2009-11-07 G. A. Diamandis , B. C. Georgalas , N. E. Mavromatos , E. Papantonopoulos , I. Pappa

Positive vacuum energy together with extra dimensions of space imply that our four-dimensional Universe is unstable, generically to decompactification of the extra dimensions. Either quantum tunneling or thermal fluctuations carry one past…

High Energy Physics - Theory · Physics 2009-11-10 Steven B. Giddings , Robert C. Myers

We argue that standard tools of holography can be used to describe fully non-perturbative microscopic models of cosmology in which a period of accelerated expansion may result from the positive potential energy of time-dependent scalar…

High Energy Physics - Theory · Physics 2022-03-23 Stefano Antonini , Petar Simidzija , Brian Swingle , Mark Van Raamsdonk

A cosmological model describing the evolution of n Ricci-flat spaces (n>1) in the presence of 1-component perfect-fluid and minimally coupled scalar field is considered. When the pressures in all spaces are proportional to the density, the…

High Energy Physics - Theory · Physics 2009-09-25 V. D. Ivashchuk , V. N. Melnikov

The energy density of the universe today may be dominated by the vacuum energy of a slowly rolling scalar field. Making a quantum expansion around such a time dependent solution is found to break fundamental symmetries of quantum field…

High Energy Physics - Phenomenology · Physics 2008-11-26 Pankaj Jain , Subhadip Mitra

We discuss a cosmological model where the universe shrinks rather than expands during the radiation and matter dominated periods. Instead, the Planck mass and all particle masses grow exponentially, with the size of atoms shrinking…

Cosmology and Nongalactic Astrophysics · Physics 2013-11-13 C. Wetterich

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 $\Phi d^{4}x$,…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Eduardo Guendelman , Pedro Labrana

We apply the complex de Broglie-Bohm formulation of quantum mechanics [1] to a spatially closed homogeneous and isotropic early Universe whose matter content are radiation and dust perfect fluids. We then show that an expanding classical…

General Relativity and Quantum Cosmology · Physics 2016-10-12 M. Fathi , S. Jalalzadeh , P. V. Moniz

The great emptiness is a possible beginning of the Universe in the infinite past of physical time. For the epoch of great emptiness particles are extremely rare and effectively massless. Only expectation values of fields and average…

General Relativity and Quantum Cosmology · Physics 2021-05-12 C. Wetterich

The idea that the cosmological term, Lambda, should be a time dependent quantity in cosmology is a most natural one. It is difficult to conceive an expanding universe with a strictly constant vacuum energy density, namely one that has…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-18 Joan Sola