Anisotropic k-essence cosmologies

doi:https://doi.org/10.1103/PHYSREVD.73.063502

Title: Anisotropic k-essence cosmologies

Full Record
Other Related Research

Abstract

We investigate a Bianchi type-I cosmology with k-essence and find the set of models which dissipate the initial anisotropy. There are cosmological models with extended tachyon fields and k-essence 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 k-essence 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 k-field and polynomial kinetic function models evolve asymptotically to Friedmann-Robertson-Walker 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 k-essence, we find the general solution in the Bianchi type-I 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:

Chimento, Luis P; Forte, Monica ^[1]

Departamento de Fisica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Pabellon I, 1428 Buenos Aires (Argentina)

Publication Date:: 2006-03-15

OSTI Identifier:: 20782606

Resource Type:: Journal Article

Journal Name:: Physical Review. D, Particles Fields

Additional Journal Information:: 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); Journal ID: ISSN 0556-2821

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 k-essence cosmologies.  United States: N. p., 2006. 
        Web.  doi:10.1103/PHYSREVD.73.063502.

Copy to clipboard


                    Chimento, Luis P, & Forte, Monica. Anisotropic k-essence cosmologies.  United States.  https://doi.org/10.1103/PHYSREVD.73.063502

Copy to clipboard


                    Chimento, Luis P, and Forte, Monica. Wed .  
        "Anisotropic k-essence cosmologies".  United States.  https://doi.org/10.1103/PHYSREVD.73.063502.

Copy to clipboard


                    
@article{osti_20782606,

  title        = {Anisotropic k-essence cosmologies},

  author       = {Chimento, Luis P and Forte, Monica},

  abstractNote = {We investigate a Bianchi type-I cosmology with k-essence and find the set of models which dissipate the initial anisotropy. There are cosmological models with extended tachyon fields and k-essence 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 k-essence 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 k-field and polynomial kinetic function models evolve asymptotically to Friedmann-Robertson-Walker 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 k-essence, we find the general solution in the Bianchi type-I 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},

  url          = {https://www.osti.gov/biblio/20782606},
  journal      = {Physical Review. D, Particles Fields},

  issn         = {0556-2821},

  number       = 6,

  volume       = 73,

  place        = {United States},

  year         = {2006},

  month        = {3}

}

Copy to clipboard

Journal Article:

https://doi.org/10.1103/PHYSREVD.73.063502

Other availability

Find in Google Scholar

Search WorldCat to find libraries that may hold this journal

Save / Share:

Export Metadata

Save to My Library

Similar records in OSTI.GOV collections:

Fine-tuning free paradigm of two-measures theory: k-essence, absence of initial singularity of the curvature, and inflation with graceful exit to the zero cosmological constant state

Journal Article Guendelman, E I ; Kaganovich, A B - Physical Review. D, Particles Fields

The dilaton-gravity sector of the two-measures field theory (TMT) is explored in detail in the context of spatially flat Friedman-Robertson-Walker (FRW) cosmology. The model possesses scale invariance which is spontaneously broken due to the intrinsic features of the TMT dynamics. The dilaton {phi} dependence of the effective Lagrangian appears only as a result of the spontaneous breakdown of the scale invariance. If no fine-tuning is made, the effective {phi}-Lagrangian p({phi},X) depends quadratically upon the kinetic term X. Hence TMT represents an explicit example of the effective k-essence resulting from first principles without any exotic term in the underlying action intendedmore »« less
https://doi.org/10.1103/PHYSREVD.75.083505
Attractor scenarios and superluminal signals in k-essence cosmology

Journal Article Kang, Jin U ; Arnold Sommerfeld Center, Department of Physics, Ludwig-Maximilians University, Theresienstrasse 37, 80333 Munich ; Vanchurin, Vitaly ; ... - Physical Review. D, Particles Fields

Cosmological scenarios with k-essence are invoked in order to explain the observed late-time acceleration of the Universe. These scenarios avoid the need for fine-tuned initial conditions (the 'coincidence problem') because of the attractorlike dynamics of the k-essence field {phi}. It was recently shown that all k-essence scenarios with Lagrangians p=L(X){phi}{sup -2}, where X{identical_to}(1/2){phi}{sub ,{mu}}{phi}{sup ,{mu}}, necessarily involve an epoch where perturbations of {phi} propagate faster than light (the 'no-go theorem'). We carry out a comprehensive study of attractorlike cosmological solutions ('trackers') involving a k-essence scalar field {phi} and another matter component. The result of this study is a complete classificationmore »« less
https://doi.org/10.1103/PHYSREVD.76.083511
Tracking quintessence and k-essence in a general cosmological background

Journal Article Das, Rupam ; Kephart, Thomas W ; Scherrer, Robert J - Physical Review. D, Particles Fields

We derive conditions for stable tracker solutions for both quintessence and k-essence in a general cosmological background, H{sup 2}{proportional_to}f({rho}). We find that tracker solutions are possible only when {eta}{identical_to}dlnf/dln{rho}{approx_equal}constant, aside from a few special cases, which are enumerated. Expressions for the quintessence or k-essence equation of state are derived as a function of {eta} and the equation of state of the dominant background component.
https://doi.org/10.1103/PHYSREVD.74.103515
What is needed of a tachyon if it is to be the dark energy?

Journal Article Copeland, Edmund J ; Garousi, Mohammad R ; Sami, M ; ... - Physical Review. D, Particles Fields

We study a dark energy scenario in the presence of a tachyon field {phi} with potential V({phi}) and a barotropic perfect fluid. The cosmological dynamics crucially depends on the asymptotic behavior of the quantity {lambda}=-M{sub p}V{sub {phi}}/V{sup 3/2}. If {lambda} is a constant, which corresponds to an inverse square potential V({phi}){proportional_to}{phi}{sup -2}, there exists one stable critical point that gives an acceleration of the Universe at late times. When {lambda}{yields}0 asymptotically, we can have a viable dark energy scenario in which the system approaches an instantaneous critical point that dynamically changes with {lambda}. If |{lambda}| approaches infinity asymptotically, the Universemore »« less
https://doi.org/10.1103/PhysRevD.71.043003
Tachyon and quintessence in brane worlds

Journal Article Chimento, Luis P ; Forte, Monica ; Richarte, Martin G ; ... - Physical Review. D, Particles Fields

Using tachyon or quintessence fields along with a barotropic fluid on the brane we examine the different cosmological stages in a Friedmann-Robertson-Walker universe, from the first radiation scenario to the later era dominated by cosmic string networks. We introduce a new algorithm to generalize previous works on exact solutions and apply it to study tachyon and quintessence fields localized on the brane. We also explore the low and high energy regimes of the solutions. Besides, we show that the tachyon and quintessence fields are driven by an inverse power law potential. Finally, we find several simple exacts solutions for tachyonmore » and/or quintessence fields.« less
https://doi.org/10.1103/PHYSREVD.79.083527

Similar Records