Anisotropic kessence cosmologies
Abstract
We investigate a Bianchi typeI cosmology with kessence and find the set of models which dissipate the initial anisotropy. There are cosmological models with extended tachyon fields and kessence having a constant barotropic index. We obtain the conditions leading to a regular bounce of the average geometry and the residual anisotropy on the bounce. For constant potential, we develop purely kinetic kessence models which are dust dominated in their early stages, dissipate the initial anisotropy, and end in a stable de Sitter accelerated expansion scenario. We show that linear kfield and polynomial kinetic function models evolve asymptotically to FriedmannRobertsonWalker cosmologies. The linear case is compatible with an asymptotic potential interpolating between V{sub l}{proportional_to}{phi}{sup {gamma}{sub l}}, in the shear dominated regime, and V{sub l}{proportional_to}{phi}{sup 2} at late time. In the polynomial case, the general solution contains cosmological models with an oscillatory average geometry. For linear kessence, we find the general solution in the Bianchi typeI cosmology when the k field is driven by an inverse square potential. This model shares the same geometry as a quintessence field driven by an exponential potential.
 Authors:
 Departamento de Fisica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Pabellon I, 1428 Buenos Aires (Argentina)
 Publication Date:
 OSTI Identifier:
 20782606
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physical Review. D, Particles Fields; Journal Volume: 73; Journal Issue: 6; Other Information: DOI: 10.1103/PhysRevD.73.063502; (c) 2006 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; ANISOTROPY; COSMOLOGICAL MODELS; COSMOLOGY; DE SITTER GROUP; DUSTS; GEOMETRY; MATHEMATICAL SOLUTIONS; NONLUMINOUS MATTER; POLYNOMIALS; POTENTIALS; SHEAR
Citation Formats
Chimento, Luis P., and Forte, Monica. Anisotropic kessence cosmologies. United States: N. p., 2006.
Web. doi:10.1103/PHYSREVD.73.063502.
Chimento, Luis P., & Forte, Monica. Anisotropic kessence cosmologies. United States. doi:10.1103/PHYSREVD.73.063502.
Chimento, Luis P., and Forte, Monica. Wed .
"Anisotropic kessence cosmologies". United States.
doi:10.1103/PHYSREVD.73.063502.
@article{osti_20782606,
title = {Anisotropic kessence cosmologies},
author = {Chimento, Luis P. and Forte, Monica},
abstractNote = {We investigate a Bianchi typeI cosmology with kessence and find the set of models which dissipate the initial anisotropy. There are cosmological models with extended tachyon fields and kessence having a constant barotropic index. We obtain the conditions leading to a regular bounce of the average geometry and the residual anisotropy on the bounce. For constant potential, we develop purely kinetic kessence models which are dust dominated in their early stages, dissipate the initial anisotropy, and end in a stable de Sitter accelerated expansion scenario. We show that linear kfield and polynomial kinetic function models evolve asymptotically to FriedmannRobertsonWalker cosmologies. The linear case is compatible with an asymptotic potential interpolating between V{sub l}{proportional_to}{phi}{sup {gamma}{sub l}}, in the shear dominated regime, and V{sub l}{proportional_to}{phi}{sup 2} at late time. In the polynomial case, the general solution contains cosmological models with an oscillatory average geometry. For linear kessence, we find the general solution in the Bianchi typeI cosmology when the k field is driven by an inverse square potential. This model shares the same geometry as a quintessence field driven by an exponential potential.},
doi = {10.1103/PHYSREVD.73.063502},
journal = {Physical Review. D, Particles Fields},
number = 6,
volume = 73,
place = {United States},
year = {Wed Mar 15 00:00:00 EST 2006},
month = {Wed Mar 15 00:00:00 EST 2006}
}

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