Consistency relation in cosmology

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

A Fluctuation-Dissipation Relation for Semiclassical Cosmology

Using the concept of open systems where the classical geometry is treated as the system and the quantum matter field as the environment, we derive a fluctuationdissipation theorem for semiclassical cosmology. This theorem which exists under very general conditions for dissipations in the dynamics of the system, and the noise and fluctuations in the environment, can be traced to the formal mathe...

The Age - Redshift Relation for Standard Cosmology

We present compact, analytic expressions for the age-redshift relation τ (z) for standard Friedmann-Lemâ itre-Robertson-Walker (FLRW) cosmology. The new expressions are given in terms of Legendre elliptic integrals and evaluate much faster than by direct numerical integration. Subject headings: cosmology: theory – large-scale structure of universe

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...