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Related papers: Cosmological model with variable vacuum pressure

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If one is willing to give up the cherished hypothesis of spatial isotropy, many interesting cosmological models can be developed beyond the simple anisotropically expanding scenarios. One interesting possibility is presented by shear-free…

Cosmology and Nongalactic Astrophysics · Physics 2015-07-22 Thiago S. Pereira , Guillermo A. Mena Marugán , Saulo Carneiro

In this paper we construct the complete evolution of the universe driven by the mass dimension one dark spinor called Elko, starting with inflation, passing by the matter dominated era and finishing with the recent accelerated expansion.…

General Relativity and Quantum Cosmology · Physics 2017-09-28 S. H. Pereira , T. M. Guimarães

We study the emission of large-scales wavelength space-time waves during the inflationary expansion of the universe, produced by back-reaction effects. As an example, we study an inflationary model with variable time scale, where the scale…

General Relativity and Quantum Cosmology · Physics 2020-06-12 Juan Ignacio Musmarra , Mauricio Bellini

General non-singular accelerating cosmological solutions for an initial cosmic period of pure vacuum birth era are derived. This vacuum era is described by a varying cosmological "constant" suggested by the Renormalisation Group flow of…

General Relativity and Quantum Cosmology · Physics 2016-11-23 Georgios Kofinas , Vasilios Zarikas

We investigate the dynamics of single and multiple scalar fields with exponential potentials, leading to power-law and assisted inflation, in loop quantum cosmology. Unlike in the classical theory, dynamical trajectories in loop quantum…

General Relativity and Quantum Cosmology · Physics 2012-07-05 Evan Ranken , Parampreet Singh

We propose a new form for equations of state (EOS) of thermodynamic systems in the Ising universality class. The new EOS guarantees the correct universality and scaling behavior close to critical points and is formulated in terms of the…

Statistical Mechanics · Physics 2014-02-07 Arnold Neumaier

Inflationary cosmology has become one of the cornerstones of modern cosmology. Inflation was the first theory within which it was possible to make predictions about the structure of the Universe on large scales, based on causal physics. The…

Astrophysics · Physics 2010-12-09 Robert H. Brandenberger

We consider cosmological evolution from the perspective of quantum information. We present a quantum circuit model for the expansion of a comoving region of space, in which initially-unentangled ancilla qubits become entangled as expansion…

High Energy Physics - Theory · Physics 2017-04-18 Ning Bao , ChunJun Cao , Sean M. Carroll , Liam McAllister

In these lectures I focus on early universe models which can explain the currently observed structure on large scales. I begin with a survey of inflationary cosmology, the current paradigm for understanding the origin of the universe as we…

High Energy Physics - Theory · Physics 2015-05-18 Robert H. Brandenberger

A very simple non-singular inflationary model is presented where the unique matter content is a radiation fluid. The model slowly contracts from a very large, almost empty and flat spacetime and realizes a bounce. It is then launched to a…

General Relativity and Quantum Cosmology · Physics 2024-03-08 Piero A. P. Molinari , Paola C. M. Delgado , Rodrigo F. Pinheiro , Nelson Pinto-Neto

We explore an effective 4D cosmological model for the universe where the variable cosmological constant governs its evolution and the pressure remains negative along all the expansion. This model is introduced from a 5D vacuum state where…

General Relativity and Quantum Cosmology · Physics 2010-03-26 Agustin Membiela , Mauricio Bellini

Abandoning the perfect fluid hypothesis, we investigate here the possibility that the dark energy equation of state (EoS) $w$ is a nonlinear function of the energy density $\rho$. To this aim, we consider four different EoS describing…

Astrophysics · Physics 2009-11-13 V. F. Cardone , C. Tortora , A. Troisi , S. Capozziello

Recent observations of Type Ia supernovae provide evidence for the acceleration of our universe, which leads to the possibility that the universe is entering an inflationary epoch. We simulate it under a ``big bounce'' model, which contains…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Beili Wang , Hongya Liu , Lixin Xu

Assuming that higher dimensions existed in the early stages of the universe where the evolution was inflationary, we construct an open, singularity-free, spatially homogeneous and isotropic cosmological model to study the effects of…

Astrophysics · Physics 2009-11-10 Koray Karaca , Selcuk Bayin

The Universe is currently in a phase of accelerated expansion, a fact that was experimentally proven in the late 1990s. Cosmological models involving scalar fields allow the description of this accelerated expansion regime in the Cosmos and…

General Relativity and Quantum Cosmology · Physics 2023-10-11 Joao R. L. Santos , S. Santos da Costa , Romario S. Santos

Following recent studies of Ford, we suggest -- in the framework of general relativity -- an inflationary cosmological model with the self-interacting spinning matter. A generalization of the standard fluid model is discussed and estimates…

General Relativity and Quantum Cosmology · Physics 2010-11-01 Yuri N. Obukhov

We investigate inflation driven by the evolution of highly excited quantum states within the framework of out of equilibrium field dynamics. The self-consistent evolution of these quantum states and the scale factor is studied analytically…

Astrophysics · Physics 2007-05-23 F. J. Cao

We propose a model for cosmic inflation which is based on an effective description of strongly interacting, nonsupersymmetric matter within the framework of dynamical abelian projection and centerization. The underlying gauge symmetry is…

High Energy Physics - Phenomenology · Physics 2007-05-23 Ralf Hofmann , Mathias Th. Keil

In the framework of a cosmological model of the Universe filled with a nonrelativistic particle soup, we easily reproduce inflation due to the quantum potential. The lightest particles in the soup serve as a driving force of this simple,…

General Relativity and Quantum Cosmology · Physics 2015-07-22 Maxim V. Eingorn , Vitaliy D. Rusov

In the paper we consider the macroscopic model of plasma of scalar charged particles, obtained by means of the statistical averaging of the microscopic equations of particle dynamics in a scalar field. On the basis of kinetic equations,…

General Relativity and Quantum Cosmology · Physics 2015-06-23 Yurii Ignat'ev , Alexander Agathonov , Mikhail Mikhailov , Dmitry Ignatyev