English
Related papers

Related papers: Solution to the Isotropy Problem for Cosmological …

200 papers

We consider homogeneous abelian vector fields in an expanding universe. We find a mechanical analogy in which the system behaves as a particle moving in three dimensions under the action of a central potential. In the case of bounded and…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 J. A. R. Cembranos , C. Hallabrin , A. L. Maroto , S. J. Núñez Jareño

We construct a model of hidden massive vector boson dark matter as a homogeneous coherent oscillation in the entire universe without any dangerous instability. We make use of a particular form of the vector boson coupling to a scalar field…

High Energy Physics - Phenomenology · Physics 2023-03-08 Kazunori Nakayama

We consider several new classes of viable vector field alternatives to the inflaton and quintessence scalar fields. Spatial vector fields are shown to be compatible with the cosmological anisotropy bounds if only slightly displaced from the…

Astrophysics · Physics 2010-11-19 Tomi S. Koivisto , David F. Mota

Homogeneous isotropic cosmological models with two torsion functions filled with scalar fields and usual gravitating matter are built and investigated in the framework of the Poincar\'e gauge theory of gravity. It is shown that by certain…

General Relativity and Quantum Cosmology · Physics 2008-11-26 A. V. Minkevich , A. S. Garkun , V. I. Kudin

We consider homogeneous non-abelian vector fields with general potential terms in an expanding universe. We find a mechanical analogy with a system of N interacting particles (with N the dimension of the gauge group) moving in three…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 J. A. R. Cembranos , A. L. Maroto , S. J. Núñez Jareño

Models with vector fields acquiring a non-vanishing vacuum expectation value along one spatial direction have been proposed to sustain a prolonged stage of anisotropic accelerated expansion. Such models have been used for realizations of…

Astrophysics · Physics 2009-04-08 Burak Himmetoglu , Carlo R. Contaldi , Marco Peloso

A coherent field over the entire universe is an attractive picture in studying the dark sector of the universe. The misalignment mechanism, which relies on inflation to achieve homogeneousness of the field, is a popular mechanism for…

Cosmology and Nongalactic Astrophysics · Physics 2023-09-11 Kunio Kaneta , Hye-Sung Lee , Jiheon Lee , Jaeok Yi

We study both the background evolution and cosmological perturbations of anisotropic inflationary models supported by coupled scalar and vector fields. The models we study preserve the U(1) gauge symmetry associated with the vector field,…

Cosmology and Nongalactic Astrophysics · Physics 2011-07-29 Burak Himmetoglu

Cosmological equations for homogeneous isotropic models filled by scalar fields and ultrarelativistic matter are investigated in the framework of gauge theories of gravity. Regular inflationary cosmological models of flat, closed and open…

General Relativity and Quantum Cosmology · Physics 2014-11-17 A. V. Minkevich

A simple gravitational model with torsion is studied, and it is suggested that it could explain the dark matter and dark energy in the universe. It can be reinterpreted as a model using the Einstein gravitational equations where spacetime…

General Relativity and Quantum Cosmology · Physics 2022-03-28 Graeme W. Milton

It is shown that cosmological equations for homogeneous isotropic models deduced in the framework of the Poincar\'e gauge theory of gravity by certain restrictions on indefinite parameters of gravitational Lagrangian take at asymptotics the…

General Relativity and Quantum Cosmology · Physics 2009-09-29 A. V. Minkevich

In a model of an Abelian vector boson with a Maxwell kinetic term and non-negative mass-squared it is demonstrated that, under fairly general conditions during inflation, a scale-invariant spectrum of perturbations for the components of a…

High Energy Physics - Phenomenology · Physics 2011-02-28 Konstantinos Dimopoulos , Jacques M. Wagstaff

In the context of a special class of tensor-multi-scalar theories of gravity for which the target-space metric admits an isometry under which the theory is invariant, we present rotating vacuum solutions, namely with no matter fields. These…

General Relativity and Quantum Cosmology · Physics 2020-02-19 Lucas G. Collodel , Daniela D. Doneva , Stoytcho S. Yazadjiev

Inflationary homogeneous isotropic cosmological models filled by scalar fields and ultrarelativistic matter are examined in the framework of gauge theories of gravitation. By using quadratic scalar field potential numerical analysis of…

General Relativity and Quantum Cosmology · Physics 2007-05-23 A. V. Minkevich , A. S. Garkun

It is shown that all vacuum solutions of Einstein field equation with a positive cosmological constant are the solutions of a model of dS gauge theory of gravity. Therefore, the model is expected to pass the observational tests on the scale…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Chao-Guang Huang , Yu Tian , Xiaoning Wu , Han-Ying Guo

The cosmological evolution of free massless vector or tensor (but not gauge) fields minimally coupled to gravity is analyzed. It is shown that there are some unstable solutions for these fields in De Sitter background. The back reaction of…

Astrophysics · Physics 2009-12-30 A. D. Dolgov

We obtain the pressures and equations of state (EoS) of charged and neutral vector boson gases in a constant magnetic field. The axial symmetry imposed to the system by the field splits the pressures in the parallel and perpendicular…

High Energy Physics - Phenomenology · Physics 2018-04-03 G. Quintero Angulo , A. Pérez Martínez , H. Pérez Rojas

I briefly outline a new physical interpretation to the average cosmological parameters for an inhomogeneous universe with backreaction. The variance in local geometry and gravitational energy between ideal isotropic observers in bound…

Cosmology and Nongalactic Astrophysics · Physics 2009-12-31 David L. Wiltshire

We construct a viable model of the vector coherent oscillation dark matter. The vector boson is coupled to the inflaton through the kinetic function so that the effective Hubble mass term is cancelled out. In order to avoid strong…

High Energy Physics - Phenomenology · Physics 2023-07-12 Naoya Kitajima , Kazunori Nakayama

Field theoretical scheme of regular Big Bang in 4-dimensional physical space-time, built in the framework of gauge approach to gravitation, is discussed. Regular bouncing character of homogeneous isotropic cosmological models is ensured by…

General Relativity and Quantum Cosmology · Physics 2007-05-23 A. V. Minkevich
‹ Prev 1 2 3 10 Next ›