Generic estimate of trans-Planckian modifications to the primordial power spectrum in inflation

  title={Generic estimate of trans-Planckian modifications to the primordial power spectrum in inflation},
  author={Richard Easther and Brian Randolph Greene and W. H. Shiu},
  journal={Physical Review D},
We derive a general expression for the power spectra of scalar and tensor fluctuations generated during inflation given an arbitrary choice of boundary condition for the mode function at a short distance. We assume that the boundary condition is specified at a short-distance cutoff at a scale $M$ which is independent of time. Using a particular prescription for the boundary condition at momentum $p = M$, we find that the modulation to the power spectra of density and gravitational wave… 

Figures from this paper

Is there an imprint of Planck-scale physics on inflationary cosmology?

We study the effects of the trans-Planckian dispersion relation on the spectrum of the primordial density perturbations during inflation. In contrast to the earlier analyses, we do not assume any

Exploring trans-Planckian physics and the curvature effect by primordial power spectrum with WMAP five-year data

The vacuum inflation with a boundary condition specified at a short-distance scale in a generally primeval non-flat Universe, and implications of the correspondingly modified primordial power

Path integral duality and Planck scale corrections to the primordial spectrum in exponential inflation

The enormous red-shifting of the modes during the inflationary epoch suggests that physics at the Planck scale may modify the standard, nearly scale-invariant, primordial, density perturbation

Renormalization of initial conditions and the trans-Planckian problem of inflation

Understanding how a field theory propagates the information contained in a given initial state is essential for quantifying the sensitivity of the cosmic microwave background to physics above the

Covariant Predictions for Planck-Scale Features in Primordial Power Spectra

In this companion to our letter (arXiv:2208.10514), we study the predicted corrections to the primordial scalar and tensor power spectra that arise from quantum gravity-motivated, natural, covariant

Where does cosmological perturbation theory break down?

It is often assumed that initial conditions for the evolution of a cosmological mode should be set at the time its physical wavelength reaches a cut-off of the order of the Planck length. Beyond that

Quantum Stress Tensor Fluctuations of a Conformal Field and Inflationary Cosmology

We discuss the additional perturbation introduced during inflation by quantum stress tensor fluctuations of a conformally invariant field such as the photon. We consider both a kinematical model,

Gauge-invariant perturbation theory for trans-Planckian inflation

The possibility that the scale-invariant inflationary spectrum may be modified due to the hidden assumptions about the Planck scale physics--dubbed as trans-Planckian inflation--has received

Predictions for Quantum Gravitational Signatures from Inflation

We compute the corrections to the primordial power spectrum that should arise in realistic inflationary scenarios if there exists a generic covariant ultraviolet (UV) cutoff, as commonly motivated by

Primordial fluctuations from deformed quantum algebras

We study the implications of deformed quantum algebras for the generation of primordial perturbations from slow-roll inflation. Specifically, we assume that the quantum commutator of the inflaton's




  • Rev. D 64, 103502
  • 2001


  • Rev. D 63, 123501
  • 2001


  • Rev. D 63, 123502
  • 2001


  • Rev. D 64, 101301
  • 2001


  • Rev. D 42, 3936
  • 1990


  • Rev D 63, 083514
  • 2001

The emphasis is pedagogical; a more formal review can be found in Ref

  • this section we review the basics of scalar field dynamics in inflationary cosmology with emphasis on the very useful Hamilton-Jacobi formalism


  • Rev. D 64, 103501
  • 2001


  • Rev. D 50, 2479
  • 1994


  • Rev. D 50, 7222
  • 1994