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Related papers: Knot Universes in Bianchi Type I Cosmology

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Loop quantum cosmology allows for arbitrary superpositions of the triad variable. We show here how these superpositions can become indistinguishable from a classical mixture by the interaction with fermions. We calculate the reduced density…

General Relativity and Quantum Cosmology · Physics 2013-01-23 Claus Kiefer , Christian Schell

A systematic dynamical system approach is applied to study the cosmology of anisotropic Bianchi I universes in which a vector field is assumed to operate on a disformal frame. This study yields a number of new fixed points, among which…

Cosmology and Nongalactic Astrophysics · Physics 2015-09-02 Tomi S. Koivisto , Federico R. Urban

We analyze the state space of a Bianchi-I universe with anisotropic sources. Here we consider an extended state space which includes null geodesics in this background. The evolution equations for all the state observables are derived.…

General Relativity and Quantum Cosmology · Physics 2016-02-09 Pavan K. Aluri , Sukanta Panda , Manabendra Sharma , Snigdha Thakur

We develop the "triangulated" version of loop quantum cosmology, recently introduced in the literature. We focus on the "dipole" cosmology, where space is a three-sphere and the triangulation is formed by two tetrahedra. We show that the…

General Relativity and Quantum Cosmology · Physics 2010-05-12 Marco Valerio Battisti , Antonino Marciano , Carlo Rovelli

We consider the dynamics of a causal bulk viscous cosmological fluid filled constantly decelerating Bianchi type I space-time. The matter component of the Universe is assumed to satisfy a linear barotropic equation of state and the state…

General Relativity and Quantum Cosmology · Physics 2008-11-26 M. K. Mak , T. Harko

The canonical theory of (N=1) supergravity, with a matrix representation for the gravitino covector-spinor, is applied to the Bianchi class A spatially homogeneous cosmologies. The full Lorentz constraint and its implications for the wave…

General Relativity and Quantum Cosmology · Physics 2016-08-15 Alfredo Macías , Eckehard W. Mielke , José Socorro

We present a reconstruction algorithm for cosmological models based on $f(\mathcal{Q})$ gravity. We specifically focus on obtaining exact Bianchi Type-I and Friedmann-Lema\^{\i}tre-Robertson-Walker solutions, finding solutions that might…

General Relativity and Quantum Cosmology · Physics 2022-05-12 Fabrizio Esposito , Sante Carloni , Roberto Cianci , Stefano Vignolo

We look for necessary conditions such that minimally coupled scalar-tensor theory with a massive scalar field and a perfect fluid in the Bianchi type I model isotropises. Then we derive the dynamical asymptotical properties of the Universe.

General Relativity and Quantum Cosmology · Physics 2007-05-23 Stephane Fay

In this study, we have demonstrated the expansion history of an axially symmetric Bianchi type-I model of the universe. Our model as of now presents an accelerating universe, which had been in the decelerating phase in the past. Roles of…

General Relativity and Quantum Cosmology · Physics 2022-11-30 Vinod Kumar Bhardwaj , Archana Dixit , Rita Rani , G. K. Goswami , Anirudh Pradhan

We consider the dynamics of a barotropic cosmological fluid in an anisotropic, Bianchi type I space-time in Eddington-inspired Born-Infeld (EiBI) gravity. By assuming an isotropic pressure distribution, we obtain the general solution of the…

General Relativity and Quantum Cosmology · Physics 2014-10-30 Tiberiu Harko , Francisco S. N. Lobo , M. K. Mak

We study quantum corrections to the classical Bianchi I and Bianchi IX universes. The modified dynamics is well-motivated from the asymptotic safety program where the short-distance behavior of gravity is governed by a non-trivial…

General Relativity and Quantum Cosmology · Physics 2016-01-06 Giulio D'Odorico , Frank Saueressig

In the cosmological scenario in $f\left( T\right) $ gravity, we find analytical solutions for an isotropic and homogeneous universe containing a dust fluid and radiation and for an empty anisotropic Bianchi I universe. The method that we…

General Relativity and Quantum Cosmology · Physics 2016-08-01 Andronikos Paliathanasis , John D. Barrow , P. G. L. Leach

Extremal black branes are of interest because they correspond to the ground states of field theories at finite charge density in gauge/gravity duality. The geometry of such a brane need not be translationally invariant in the spatial…

High Energy Physics - Theory · Physics 2015-06-03 Norihiro Iizuka , Shamit Kachru , Nilay Kundu , Prithvi Narayan , Nilanjan Sircar , Sandip P. Trivedi

The models of cyclic universes and cyclic multiverses based on the alternative gravity theories of varying constants are considered.

General Relativity and Quantum Cosmology · Physics 2017-08-18 Mariusz P. Dabrowski

Knot physics is the theory of the universe that not only unified all the fundamental interactions but also explores the underlying physics of quantum mechanics. In knot physics, the most important physical result is the unification of…

General Physics · Physics 2019-09-05 Su-Peng Kou

``One could imagine that as a result of enormously extended astronomical experience, the entire universe consists of countless identical copies of our Milky Way, that the infinite space can be partitioned into cubes each containing an…

Astrophysics · Physics 2007-05-23 Jean-Pierre Luminet , Boudewijn F. Roukema

We consider topological structure of classical vacuum solutions in quantum chromodynamics. Topologically non-equivalent vacuum configurations are classified by non-trivial second and third homotopy groups for coset of the color group SU(N)…

High Energy Physics - Theory · Physics 2013-09-30 L. P. Zou , P. M. Zhang , D. G. Pak

A general formalism to investigate Bianchi type $VI_h$ universes is developed in an extended theory of gravity. A minimally coupled geometry and matter field is considered with a rescaled function of $f(R,T)$ substituted in place of the…

General Physics · Physics 2018-03-28 B. Mishra , S. K. Tripathy , Sankarsan Tarai

The dynamics of cosmological models with isotropic matter sources (perfect fluids) is extensively studied in the literature; in comparison, the dynamics of cosmological models with anisotropic matter sources is not. In this paper we…

General Relativity and Quantum Cosmology · Physics 2011-02-16 Simone Calogero , J. Mark Heinzle

We investigate structure formation in a one dimensional model of a matter-dominated universe using a quasi-newtonian formulation. In addition to dark matter, luminous matter is introduced to examine the potential bias in the distributions.…

Cosmology and Nongalactic Astrophysics · Physics 2016-06-29 Yui Shiozawa , Bruce N. Miller