Tachyon inflation: tests and comparison with single scalar field inflation

  title={Tachyon inflation: tests and comparison with single scalar field inflation},
  author={D.A.Steer and F.Vernizzi},
We compare the standard single scalar field inflationary predictions with those of an inflationary phase driven by a tachyon field. A slow-roll formalism is defined for tachyon inflation, and we derive the spectra of scalar and tensor perturbations as well as the consistency relations. At lowest order the predictions of standard and tachyon inflation are shown to be the same. Higher order deviations are present and their observational relevance is discussed. We then study some typical inflationary… 

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