Cover Image

Scalar-induced gravitational waves in a ΛCDM cosmology

We reconsider the gravitational wave spectrum induced by scalar perturbations in spatially flat Friedmann-Lemaître-Robertson-Walker spacetimes, focusing on the matter- and Λ-dominated epochs. During matter domination, subhorizon modes are not free, and a commonly applied approximation for the deriv...

Full description

Saved in:
Bibliographic Details
Main Authors: Sipp, Marvin (Author) , Schäfer, Björn Malte (Author)
Format: Article (Journal)
Language:English
Published: 24 March 2023
In: Physical review
Year: 2023, Volume: 107, Issue: 6, Pages: 1-12
ISSN:2470-0029
DOI:10.1103/PhysRevD.107.063538
Online Access:Verlag, lizenzpflichtig, Volltext: https://doi.org/10.1103/PhysRevD.107.063538
Verlag, lizenzpflichtig, Volltext: https://link.aps.org/doi/10.1103/PhysRevD.107.063538
Get full text
Author Notes:Marvin Sipp, Björn Malte Schäfer
Description
Summary:We reconsider the gravitational wave spectrum induced by scalar perturbations in spatially flat Friedmann-Lemaître-Robertson-Walker spacetimes, focusing on the matter- and Λ-dominated epochs. During matter domination, subhorizon modes are not free, and a commonly applied approximation for the derivative of the tensor perturbation is flawed. We show analytically that this leads to a significant overestimation of the energy density spectrum. In addition, we demonstrate that gauge-dependent nonoscillating tensor perturbations appear in the presence of a cosmological constant. Complementing the analytical calculations, we compute the according present-day spectrum numerically for a Planck-like ΛCDM cosmology, finding that nonoscillating growing modes appear during the transition between matter and Λ domination in conformal Newtonian gauge.
Item Description:Gesehen am 24.05.2023
Physical Description:Online Resource
ISSN:2470-0029
DOI:10.1103/PhysRevD.107.063538

Similar Items