Statistical Anisotropy of Primordial Gravitational Waves from Generalized δN Formalism.
Phys Rev Lett
; 132(23): 231003, 2024 Jun 07.
Article
in En
| MEDLINE
| ID: mdl-38905658
ABSTRACT
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 nonvanishing linear polarization and the qualitative difference between single- and multigauge field models.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Language:
En
Journal:
Phys Rev Lett
Year:
2024
Document type:
Article
Affiliation country:
Japón