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Related papers: Universe of Fluctuations II

200 papers

In accordance with known phenomenological facts on leptons and quarks in the Standard Model as well as on the scale of neutrino masses and introducing the supersymmetry, we logically substantiate the unique composition of fundamental…

High Energy Physics - Phenomenology · Physics 2011-11-03 V. V. Kiselev , V. V. Shakirov

We present the Heisenberg-picture approach to the quantum evolution of the scalar fields in an expanding FRW universe which incorporates relatively simply the initial quantum conditions such as the vacuum state, the thermal equilibrium…

General Relativity and Quantum Cosmology · Physics 2009-10-30 K. H. Cho , J. Y. Ji , S. P. Kim , C. H. Lee , J. Y. Ryu

Structure in the Universe is widely believed to have originated from quantum fluctuations during an early epoch of accelerated expansion. Yet, the patterns we observe today do not distinguish between quantum or classical primordial…

High Energy Physics - Theory · Physics 2020-07-01 Daniel Green , Rafael A. Porto

In this paper, we calculate the spectrum of scalar field fluctuations in a bouncing, asymptotically flat Universe, and investigate the dependence of the result on changes in the physics on length scales shorter than the Planck length which…

High Energy Physics - Theory · Physics 2009-11-07 Robert H Brandenberger , Sergio E. Joras , Jerome Martin

Torsion arising from fermionic matter in the Einstein-Cartan formulation of general relativity is considered in the context of Robertson-Walker geometries and the early Universe. An ambiguity in the way torsion arising from hot fermionic…

General Relativity and Quantum Cosmology · Physics 2010-12-06 Brian P. Dolan

It is generally believed that one cannot obtain a large Universe from quantum cosmological models without an inflationary phase in the classical expanding era because the typical size of the Universe after leaving the quantum regime should…

General Relativity and Quantum Cosmology · Physics 2009-04-29 Nelson Pinto-Neto

Axion-like degrees of freedom generally interact with fermions through a shift symmetric coupling. As a consequence, a time-dependent axion will lead to the generation of fermions by amplifying their vacuum fluctuations. We provide the…

Cosmology and Nongalactic Astrophysics · Physics 2024-08-09 Aditya Kulkarni , Lorenzo Sorbo

In the present paper, we study a Friedmann-Lema\^itre-Robertson-Walker (FLRW) quantum cosmology model with positively curved spatial sections. The matter content of the model is given by a radiation fluid, a Generalized Chaplygin gas, and…

General Relativity and Quantum Cosmology · Physics 2026-05-26 D. L. Canedo , G. Oliveira-Neto , G. A. Monerat , E. V. Corrêa Silva

The early Universe inflation is well known as a promising theory to explain the origin of large scale structure of the Universe, a causal theory for the origin of primordial density fluctuations which may explain the observed density…

Astrophysics · Physics 2007-05-23 Xin-he Meng

We point out that, due to the nonlinearity of the Einstein equations, a homogeneous approximation in cosmology leads to the appearance of an additional term in the Friedmann equation. This new term is associated with the spatial…

Astrophysics · Physics 2015-06-24 Gyula Bene , Viktor Czinner , Matyas Vasuth

We present a brief history of the construction of models of the universe, followed by calculations of quantitative characteristics of basic geometric and kinematic properties of the Standard Cosmological Model ($\Lambda$CDM). Using the…

General Relativity and Quantum Cosmology · Physics 2026-04-23 D. I. Nagirner , S. G. Jorstad , A. V. Dementyev

We develop a non-singular bouncing cosmology using a non-trivial coupling of general relativity to fermionic fields. The usual Big Bang singularity is avoided thanks to a negative energy density contribution from the fermions. Our theory is…

General Relativity and Quantum Cosmology · Physics 2014-12-10 Stephon Alexander , Cosimo Bambi , Antonino Marciano , Leonardo Modesto

In most current models of inflation based on a weakly self-coupled scalar matter field minimally coupled to gravity, the period of inflation lasts so long that, at the beginning of the inflationary period, the physical wavelengths of…

High Energy Physics - Theory · Physics 2008-11-26 Jerome Martin , Robert H. Brandenberger

We generalize the big-bang model in a previous paper by extending the real vacuum scalar field to a complex vacuum scalar field, within the FLRW framework. The phase dynamics of the scalar field, which makes the universe a superfluid, is…

General Relativity and Quantum Cosmology · Physics 2012-10-11 Kerson Huang , Hwee-Boon Low , Roh-Suan Tung

A selfconsistent system of equations describing evolution of linear spherically symmetric perturbations in Fridmann world by an arbitrary equation of state is obtained. The perturbations singular part corresponding to massive particle-like…

General Relativity and Quantum Cosmology · Physics 2015-03-17 Yu. G. Ignatyev , N. Elmakhi

The expansion of the closed two-component universe has been considered. The potential barrier of the expansion has been investigated and its overcoming condition has been obtained. The restrictions on the Friedmann integrals, cosmological…

General Relativity and Quantum Cosmology · Physics 2009-09-29 O. B. Karpov

In the brane-world scenario, our universe is understood as a three dimensional hypersurface embedded in a higher dimensional space-time. The fluctuations of the brane along the extra dimensions are seen from the four-dimensional point of…

High Energy Physics - Phenomenology · Physics 2007-05-23 J. A. R. Cembranos , A. Dobado , A. L. Maroto

In this report we advance the current repertoire of quantum cosmological models to incorporate inhomogenous field modes in a supersymmetric manner. In particular, we introduce perturbations about a supersymmetric FRW model. A quantum state…

General Relativity and Quantum Cosmology · Physics 2009-12-30 P. V. Moniz

We give a consistent description of how the inflationary Universe emerges in quantum cosmology. This involves two steps: Firstly, it is shown that a sensible probability peak can be obtained from the cosmological wave function. This is…

General Relativity and Quantum Cosmology · Physics 2009-10-31 A. Barvinsky , A. Kamenshchik , C. Kiefer

The standard Friedmann universe embedded in a five dimensional and constant curvature bulk is examined without any a priori junction condition between the brane and the bulk. A geometrical explanation for the accelerated expansion of the…

Astrophysics · Physics 2008-11-26 M. D. Maia , Edmundo M. Monte , J. M. F. Maia