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DOE OSTI · 1980167

Kinetically driven ekpyrosis

Shlivko, David
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Abstract

We explore the possibility of a scalar field driving ekpyrotic contraction through a noncanonical kinetic energy density rather than a negative potential. We find that this kinetically driven ekpyrosis (“k-ekpyrosis”) can be achieved in a variety of models, including scalar field theories with power-law, polynomial, or Dirac-Born-Infeld (DBI-)like kinetic terms in the action. Of these examples, the ekpyrotic phase is best sustained in power-law models, which can generate large and constant equation-of-state parameters, followed by DBI-like models, which can exhibit dynamical attractors toward similarly large equations of state. Here we show that for a broad class of theories including these examples, phases of k-ekpyrosis are accompanied by preceding or concurrent phases of superluminality.

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71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS79 ASTRONOMY AND ASTROPHYSICScosmologyevolution of the universe

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Shlivko, David. 2022-08-03. Kinetically driven ekpyrosis. https://doi.org/10.1103/physrevd.106.043508

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