Primordial gravitational waves in bimetric gravity

Journal Article · Tue Sep 01 04:00:00 EDT 2015 · Journal of Cosmology and Astroparticle Physics

DOI:https://doi.org/10.1088/1475-7516/2015/09/015· OSTI ID:22525479

Sakakihara, Yuki ^[1]; Soda, Jiro ^[2]

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1. Department of Physics, Kyoto University, Kyoto 606-8502 (Japan)
2. Department of Physics, Kobe University, Kobe 657-8501 (Japan)

We study primordial tensor power-spectra generated during inflation in bimetric gravity. More precisely, we examine a homogeneous expanding spacetime in a minimal bimetric model with an inflaton and calculate tensor perturbations on the homogeneous background under slow-roll approximation. In terms of the mass eigenstates, only the power-spectrum of the massless state remains constant and both the power-spectrum of the massive state and the cross power-spectrum rapidly decay during inflation. The amplitude of the physical power-spectrum is suppressed due to the flavor mixing. All power-spectra in the flavor eigenstates coincide with each other up to the first order of the slow-roll parameter.

• OSTI ID: 22525479
• Journal Information: Journal of Cosmology and Astroparticle Physics, Journal Name: Journal of Cosmology and Astroparticle Physics Journal Issue: 09 Vol. 2015; ISSN 1475-7516
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
AMPLITUDES
APPROXIMATIONS
COSMOLOGICAL INFLATION
DISTURBANCES
EIGENSTATES
ENERGY SPECTRA
FLAVOR MODEL
GRAVITATIONAL WAVES
MASS
SPACE-TIME
TENSORS