Consistency relation in general braneworld inflation

Consistency relation in general braneworld inflation

1550-7998=20 We study gravitational perturbations in general braneworlds carrying a perturbation of the de Sitter universe. We derive our results from a full five-dimensional quantum field theory, and exhibit explicit formulas for the scalar and tensor power spectra. We show by explicit calculation that the dark radiation induced by our perturbation is zero, which implies that the deformation a...

The consistency relation in braneworld inflation

Degeneracy of consistency equations in braneworld inflation

In a Randall–Sundrum type II inflationary scenario we compute perturbation amplitudes and spectral indices up to next-to-lowest order in the slowroll parameters, starting from the well-known lowest-order result for a de Sitter brane. Using two different prescriptions for the tensor amplitude, we show that the braneworld consistency equations are not degenerate with respect to the standard relat...

Non-gaussianity consistency relation for multifield inflation.

While detection of the "local form" bispectrum of primordial perturbations would rule out all single-field inflation models, multifield models would still be allowed. We show that multifield models described by the δN formalism obey an inequality between fNL and one of the local-form trispectrum amplitudes, τNL, such that τNL >1/2(6/5fN)(2) with a possible logarithmic scale dependence, provided...

Natural braneworld inflation and baryogenesis

In natural inflation models, the inflaton is a pseudo Nambu-Goldstone boson and the flatness of the potential is protected by shift symmetries. In this framework, a successful inflation requires the global symmetry to be spontaneously broken at a scale close to the Planck mass. Such a high value of the spontaneous breaking scale may not be legitimate in an effective field theory. On the other h...