The new ekpyrotic ghost

Kallosh, Renata; Linde, Andrei; Kang, Jin U; Mukhanov, Viatcheslav

doi:10.1088/1475-7516/2008/04/018

Title: The new ekpyrotic ghost

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Abstract

The new ekpyrotic scenario attempts to solve the singularity problem by involving violation of the null energy condition in a model which combines the ekpyrotic/cyclic scenario with the ghost condensate theory and the curvaton mechanism of production of adiabatic perturbations of the metric. The Lagrangian of this theory, as well as of the ghost condensate model, contains a term with higher derivatives, which was added to the theory to stabilize its vacuum state. We found that this term may affect the dynamics of the cosmological evolution. Moreover, after a proper quantization, this term results in the existence of a new ghost field with negative energy, which leads to a catastrophic vacuum instability. We explain why one cannot treat this dangerous term as a correction valid only at small energies and momenta below some UV cutoff, and demonstrate the problems arising when one attempts to construct a UV completion of this theory.

Authors:

Kallosh, Renata; Linde, Andrei ^[1]; Kang, Jin U; Mukhanov, Viatcheslav ^[2]

Department of Physics, Stanford University, Stanford, CA 94305 (United States)
Arnold-Sommerfeld-Center for Theoretical Physics, Department of Physics, Ludwig-Maximilians-Universitaet Muenchen, Theresienstrasse 37, D-80333 Munich (Germany)

Publication Date:: Tue Apr 15 00:00:00 EDT 2008

OSTI Identifier:: 22137843

Resource Type:: Journal Article

Journal Name:: Journal of Cosmology and Astroparticle Physics

Additional Journal Information:: Journal Volume: 2008; Journal Issue: 04; Other Information: Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 1475-7516

Country of Publication:: United States

Language:: English

Subject:: 79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; BRANES; DISTURBANCES; GALACTIC EVOLUTION; INSTABILITY; LAGRANGIAN FUNCTION; METRICS; QUANTIZATION; SINGULARITY; VACUUM STATES

Citation Formats


                    Kallosh, Renata, Linde, Andrei, Kang, Jin U, and Mukhanov, Viatcheslav. The new ekpyrotic ghost.  United States: N. p., 2008. 
        Web.  doi:10.1088/1475-7516/2008/04/018.

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                    Kallosh, Renata, Linde, Andrei, Kang, Jin U, & Mukhanov, Viatcheslav. The new ekpyrotic ghost.  United States.  https://doi.org/10.1088/1475-7516/2008/04/018

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                    Kallosh, Renata, Linde, Andrei, Kang, Jin U, and Mukhanov, Viatcheslav. 2008.  
        "The new ekpyrotic ghost".  United States.  https://doi.org/10.1088/1475-7516/2008/04/018.

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@article{osti_22137843,

  title        = {The new ekpyrotic ghost},

  author       = {Kallosh, Renata and Linde, Andrei and Kang, Jin U and Mukhanov, Viatcheslav},

  abstractNote = {The new ekpyrotic scenario attempts to solve the singularity problem by involving violation of the null energy condition in a model which combines the ekpyrotic/cyclic scenario with the ghost condensate theory and the curvaton mechanism of production of adiabatic perturbations of the metric. The Lagrangian of this theory, as well as of the ghost condensate model, contains a term with higher derivatives, which was added to the theory to stabilize its vacuum state. We found that this term may affect the dynamics of the cosmological evolution. Moreover, after a proper quantization, this term results in the existence of a new ghost field with negative energy, which leads to a catastrophic vacuum instability. We explain why one cannot treat this dangerous term as a correction valid only at small energies and momenta below some UV cutoff, and demonstrate the problems arising when one attempts to construct a UV completion of this theory.},

  doi          = {10.1088/1475-7516/2008/04/018},

  url          = {https://www.osti.gov/biblio/22137843},
  journal      = {Journal of Cosmology and Astroparticle Physics},

  issn         = {1475-7516},

  number       = 04,

  volume       = 2008,

  place        = {United States},

  year         = {Tue Apr 15 00:00:00 EDT 2008},

  month        = {Tue Apr 15 00:00:00 EDT 2008}

}

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