Horizon-preserving dualities and perturbations in non-canonical scalar field cosmologies

  title={Horizon-preserving dualities and perturbations in non-canonical scalar field cosmologies},
  author={Ghazal Geshnizjani and William H. Kinney and Azadeh Moradinezhad Dizgah},
  journal={Journal of Cosmology and Astroparticle Physics},
We generalize the cosmological duality between inflation and cyclic contraction under the interchange a↔H to the case of non-canonical scalar field theories with varying speed of sound. The single duality in the canonical case generalizes to a family of three dualities constructed to leave the cosmological acoustic horizon invariant. We find three classes of models: (I) DBI inflation, (II) the non-canonical generalization of cyclic contraction, and (III) a new cosmological solution with rapidly… 
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