One-loop corrections to the primordial tensor spectrum from massless isocurvature fields

Abstract

We study one-loop corrections to the two-point correlation function of tensor perturbations in primordial cosmology induced by massless spectator matter fields. Using the Schwinger-Keldysh formalism in cosmological perturbation theory, we employ dimensional regularization and cutoff regularization to study the finite quantum corrections at one-loop arising from isocurvature fields of the massless scalar, fermion and abelian gauge field which are freely propagating on the FRW spacetime. For all cases, we find a logarithmic running of the form $\frac{C}{q^3}\frac{H^4}{M_p^4}\log \left(\frac{H}{\mu }\right)$ where $C$ is a negative constant related to the beta function, $H$ is the Hubble parameter at horizon exit and $\mu$ is the renormalization scale.

33 pages, 2 figures: improved discussion of the covariant cutoff regularization method, some reorganization of materials, references added

References in corpus (5)

• The "in-in" Formalism and Cosmological Perturbations
• Cosmology With Many Light Scalar Fields: Stochastic Inflation and Loop Corrections
• Quantum Cosmological Correlations in an Inflating Universe: Can fermion and gauge fields loops give a scale free spectrum?
• IR Divergence in Inflationary Tensor Perturbations from Fermion Loops
• Noncommutative spacetime geometry and one-loop effects in primordial cosmology

Cited by in corpus (2)

• Quantum corrections to the primordial tensor spectrum: Open EFTs & Markovian decoupling of UV modes
• CFTs Blueshift Tensor Fluctuations Universally