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We investigate the cosmological reconstruction in anisotropic universe for both homogeneous and inhomogeneous content of the universe. Special attention is attached to three interesting cases: Bianchi type-I, Bianchi type-III and…

General Relativity and Quantum Cosmology · Physics 2012-11-29 M. E. Rodrigues , M. J. S. Houndjo , D. Saez-Gomez , F. Rahaman

We study Bianchi I type brane cosmologies with scalar matter self-interacting through combinations of exponential potentials. Such models correspond in some cases to inflationary universes. We discuss the conditions for accelerated…

General Relativity and Quantum Cosmology · Physics 2009-11-10 J. M. Aguirregabiria , Ruth Lazkoz

We consider here the dynamics of some homogeneous and isotropic cosmological models with $N$ interacting classical scalar fields non-minimally coupled to the spacetime curvature, as an attempt to generalize some recent results obtained for…

General Relativity and Quantum Cosmology · Physics 2007-05-23 L. Brenig , A. Figueiredo , E. Gunzig , T. M. Rocha Filho , Alberto Saa

A homogeneous and isotropic quantum cosmological system (universe) initially filled with a uniform scalar field that has a potential in the power law representation is considered. Depending on the epoch, this scalar field yields barotropic…

General Relativity and Quantum Cosmology · Physics 2025-10-20 V. E. Kuzmichev , V. V. Kuzmichev

We study in this article a class of homogeneous, but anisotropic cosmological models in which shear viscosity is included. Within the matter content we consider a component (the quintessence component) determined by the barotropic equations…

Astrophysics · Physics 2009-10-31 Mauricio Cataldo , Sergio del Campo

The combination of detections of anisotropy in the Cosmic Microwave Background radiation and observations of the large-scale distribution of galaxies probes the primordial density fluctuations of the universe on spatial scales varying by…

Astrophysics · Physics 2008-11-26 Eric Gawiser , Joseph Silk

The Lorentzian Hamiltonian constraint is solved for isotropic loop quantum cosmology coupled to a massless scalar field. As in the Euclidean case, the discreteness of quantum geometry removes the classical singularity from the quantum…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Franz Hinterleitner , Seth Major

The long-wavelength coherent overdensity and tidal force, which are not direct observables for a finite-volume survey, affect time evolution of cosmic structure formation and therefore clustering observables through the mode coupling. In…

Cosmology and Nongalactic Astrophysics · Physics 2020-06-09 Shogo Masaki , Takahiro Nishimichi , Masahiro Takada

This article describes the theory of cosmological perturbations around a homogeneous and anisotropic universe of the Bianchi I type. Starting from a general parameterisation of the perturbed spacetime a la Bardeen, a complete set of gauge…

Astrophysics · Physics 2008-11-26 Thiago S. Pereira , Cyril Pitrou , Jean-Philippe Uzan

A model of Universe with a small eccentricity due to the presence of a magnetic field at the decoupling time (i.e. an Ellipsoidal Universe) has been recently proposed for the solution of the low quadrupole anomaly of the angular power…

Astrophysics · Physics 2008-12-18 Alessandro Gruppuso

The spinorial version of the conformal vacuum Einstein field equations are used to construct a system of quasilinear wave equations for the various conformal fields. As a part of the analysis we also show how to construct a subsidiary…

General Relativity and Quantum Cosmology · Physics 2015-09-23 Edgar Gasperin , Juan Antonio Valiente Kroon

We consider the no-boundary proposal for homogeneous isotropic closed universes with a cosmological constant and a scalar field with a quadratic potential. In the semi-classical limit, it predicts classical behavior at late times if the…

High Energy Physics - Theory · Physics 2008-11-26 James B. Hartle , S. W. Hawking , Thomas Hertog

We revisit spatially flat, anisotropic cosmologies within the framework of mini-superspace. Putting special emphasis on the symmetries of the mini-superspace action and on the associated conservation laws, we unveil a new class of rotating…

High Energy Physics - Theory · Physics 2022-10-26 Alberto Nicolis , Federico Piazza , Kenza Zeghari

The standard cosmological model assumes a homogeneous and isotropic universe as the background spacetime on large scales called the cosmological principle. However, some observations suggest the possibility of an inhomogeneous and…

Cosmology and Nongalactic Astrophysics · Physics 2022-07-08 Koki Yamashita , Yue Nan , Yuuki Sugiyama , Kazuhiro Yamamoto

In this paper we have considered an anisotropic space-time model of the Universe in presence of Brans-Dicke (BD) scalar field $\phi$, causal viscous fluid and barotropic fluid. We have shown that irrespective of fluid the causality theory…

General Relativity and Quantum Cosmology · Physics 2011-09-27 Shuvendu Chakraborty , Ujjal Debnath

We calculate the anisotropies in the cosmic microwave background induced by long-wavelength primordial gravitational waves in a universe with negative spatial curvature, such as are produced in the ``open inflation'' scenario. The impact of…

Astrophysics · Physics 2009-10-30 Wayne Hu , Martin White

We present the model of anisotropic universe with string fluid as source of matter within the framework of scalar-tensor theory of gravitation. Exact solution of field equations are obtained by applying Berman's law of variation of Hubble's…

General Relativity and Quantum Cosmology · Physics 2015-06-12 Anil Kumar Yadav

We study homogeneous cosmological models featuring shift-symmetric scalar fields (or, superfluids) in relative motion. In the presence of anisotropy this universe generally features rotation, in the sense that the principal axes of…

Cosmology and Nongalactic Astrophysics · Physics 2025-11-24 Jose Beltrán Jiménez , Federico Piazza , Javier Vecino

We introduce the set of constraints the wave function of the Universe has to satisfy in order to describe an Universe undergoing through the process of spontaneous breaking of supersymmetry and discuss the way this may lead to the emergence…

General Relativity and Quantum Cosmology · Physics 2007-05-23 O. Bertolami , P. V. Moniz

We prove new estimates for the volume of a Lorentzian manifold and show especially that cosmological spacetimes with crushing singularities have finite volume.

Differential Geometry · Mathematics 2015-06-26 Claus Gerhardt