Statistical anisotropy of primordial gravitational waves from generalized $δN$ formalism

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Tanaka, Takahiro, Urakawa, Yuko
Format: Preprint
Published: 2023
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866914923084251136
author Tanaka, Takahiro
Urakawa, Yuko
author_facet Tanaka, Takahiro
Urakawa, Yuko
contents In this letter, we demonstrate how to use the generalized $δN$ formalism, which enables us to compute the evolution of all the large scale fluctuations, including gravitational waves, solely by solving the evolution of the background homogeneous Universe. Using the Noether charge density, we derive an analytic formula which describes the mapping between the fluctuations at the horizon crossing and the sourced gravitational waves at the end of inflation. This formula can apply also to an inflation model with an anisotropic background. Using this formula, we discuss the condition for the non-vanishing linear polarization and the qualitative difference between single- and multi-gauge field models.
format Preprint
id arxiv_https___arxiv_org_abs_2309_08497
institution arXiv
publishDate 2023
record_format arxiv
spellingShingle Statistical anisotropy of primordial gravitational waves from generalized $δN$ formalism
Tanaka, Takahiro
Urakawa, Yuko
General Relativity and Quantum Cosmology
Cosmology and Nongalactic Astrophysics
High Energy Physics - Phenomenology
High Energy Physics - Theory
In this letter, we demonstrate how to use the generalized $δN$ formalism, which enables us to compute the evolution of all the large scale fluctuations, including gravitational waves, solely by solving the evolution of the background homogeneous Universe. Using the Noether charge density, we derive an analytic formula which describes the mapping between the fluctuations at the horizon crossing and the sourced gravitational waves at the end of inflation. This formula can apply also to an inflation model with an anisotropic background. Using this formula, we discuss the condition for the non-vanishing linear polarization and the qualitative difference between single- and multi-gauge field models.
title Statistical anisotropy of primordial gravitational waves from generalized $δN$ formalism
topic General Relativity and Quantum Cosmology
Cosmology and Nongalactic Astrophysics
High Energy Physics - Phenomenology
High Energy Physics - Theory
url https://arxiv.org/abs/2309.08497