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We propose a cosmological model in the framework of Poincar\'e gauge gravity, in which cosmological constant, inflaton, and dark matter candidate all naturally originate. Cosmological constant originates in the process of breaking of the…

General Relativity and Quantum Cosmology · Physics 2024-03-08 Hongchao Zhang , Tao Zhu , Anzhong Wang

We provide a cosmological implementation of the evolutionary quantum gravity, describing an isotropic Universe, in the presence of a negative cosmological constant and a massive (preinflationary) scalar field. We demonstrate that the…

General Relativity and Quantum Cosmology · Physics 2015-06-22 Francesco Cianfrani , Giovanni Montani , Fabrizio Pittorino

Over the past three years we have determined the basic features of our Universe. It is 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;…

Astrophysics · Physics 2008-11-26 Michael S. Turner

Warm inflation has normalized two ideas in cosmology, that in the early universe the initial primordial density perturbations generally could be of classical rather than quantum origin and that during inflation, particle production from…

High Energy Physics - Phenomenology · Physics 2023-06-23 Arjun Berera

We consider a warm inflationary scenario in which the two dominant matter components present in the early Universe, the scalar field, and the radiation fluid, evolve with different four-velocities. This cosmological system is mathematically…

General Relativity and Quantum Cosmology · Physics 2021-03-15 Tiberiu Harko , Haidar Sheikhahmadi

In inflationary cosmology, the rapid expansion of the early universe resulted in the spontaneous production of cosmological particles from vacuum fluctuations, observable today in the cosmic microwave background anisotropies. The analogue…

Observations of the cosmic microwave sky are revealing the primordial non-uniformities from which all structure in the Universe grew. The only known physical mechanism for generating the inhomogeneities we see involves the amplification of…

Astrophysics · Physics 2009-10-31 Neil Turok

A model for a flat isotropic universe with a negative cosmological constant $\Lambda$ and a massless scalar field as sole matter content is studied within the framework of Loop Quantum Cosmology. By application of the methods introduced for…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Eloisa Bentivegna , Tomasz Pawlowski

Cosmological inflation remains to be a unique mechanism of generation of plausible initial conditions in the early universe. In particular, it generates the primordial quasiclassical perturbations with power spectrum determined by the…

Cosmology and Nongalactic Astrophysics · Physics 2010-03-23 Yuri Shtanov

I propose a unified model of particle physic and cosmology based on both a new extension of the standard particle model and the fundamental principle of the standard cosmology. Beyond the SM, I introduce several species of dark fields with…

General Physics · Physics 2025-05-13 Wei-Min Yang

We prove that in the Hartle-Hawking approach to quantum cosmology the existence of an inflationary phase is a general property of minisuperspace models given by a closed Friedmann-Robertson-Walker universe containing a massless scalar field…

General Relativity and Quantum Cosmology · Physics 2010-04-06 Giampiero Esposito , Giovanni Platania

We show that it is possible to realize an inflationary scenario even without conversion of the false vacuum energy to radiation. Such cosmological models have a deflationary stage in which $Ha^2$ is decreasing and radiation produced by…

General Relativity and Quantum Cosmology · Physics 2010-04-06 Boris Spokoiny

The thermodynamic behavior of vacuum decaying cosmologies is investigated within a manifestly covariant formulation. Such a process corresponds to a continuous irreversible energy flow from the vacuum component to the created matter…

General Relativity and Quantum Cosmology · Physics 2009-10-28 J. A. S. Lima

We investigate the possibility of gravitationally generated particle production via the mechanism of nonminimal torsion--matter coupling. An intriguing feature of this theory is that the divergence of the matter energy--momentum tensor does…

General Relativity and Quantum Cosmology · Physics 2021-07-06 Tiberiu Harko , Francisco S. N. Lobo , Emmanuel N. Saridakis

The process of quantum creation of a qusihomogeneous inflationary universe near a cosmological singularity is considered. It is shown that during the evolution quantum fluctuations of spatial topologies increase and the universe acquires…

General Relativity and Quantum Cosmology · Physics 2007-05-23 A. A. Kirillov

In the present work, particle creation mechanism has been employed to the Universe as a thermodynamical system. The Universe is considered to be a spatially flat FRW model and cosmic fluid is chosen as a perfect fluid with a barotropic…

General Physics · Physics 2016-05-04 Subhajit Saha , Subenoy Chakraborty

The quantum cosmology of the flat Friedmann-Lema{\^i}tre-Robertson-Walker Universe, filled with a scalar field, is considered in the de Broglie-Bohm (dBB) interpretation framework. A stiff-matter quantum bounce solution is obtained. The…

General Relativity and Quantum Cosmology · Physics 2023-07-24 G. S. Vicente , Rudnei O. Ramos , Vitória N. Magalhães

A cosmological model with van der Waals gas and dust has been studied in the context of a three-component autonomous non-linear dynamical system involving the time evolution of the particle number density, the Hubble parameter and the…

General Relativity and Quantum Cosmology · Physics 2019-11-13 Rossen I. Ivanov , Emil M. Prodanov

In this talk I review the present status of inflationary cosmology and its emergence as the basic paradigm behind the Standard Cosmological Model, with parameters determined today at better than 10% level from CMB and LSS observations.

High Energy Physics - Phenomenology · Physics 2010-12-09 Juan Garcia-Bellido

We have studied the evolution of the Universe in the generalized Einstein action of the form $R+\beta R^2$, where $R$ is the scalar curvature and $\beta=\rm const.$. We have found exact cosmological solutions that predict the present cosmic…

High Energy Physics - Theory · Physics 2008-11-21 Arbab I. Arbab
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