Fluctuation Spectrum From a Scalar-Tensor Bimetric Gravity Theory

Abstract

Predictions of the CMB spectrum from a bimetric gravity theory (BGT) [1] are presented. The initial inflationary period in BGT is driven by a vanishingly small speed of gravitational waves v g in the very early universe. This initial inflationary period is insensitive to the choice of scalar field potential and initial values of the scalar field. After this initial period of inflation, v g will increase rapidly and the effects of a potential will become important. We show that a quadratic potential introduced into BGT yields an approximately flat spectrum with inflation parameters: n s = 0.98, n t = −0.027, α s = −3.2 × 10 −4 and α t = −5.0 × 10 −4 , with r ≥ 0.014.

s-Process in low-metallicity stars - I. Theoretical predictions

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Variable Speed of Light Cosmology and Bimetric Gravity: An Alternative to Standard Inflation

“…In the scalar-tensor bimetric gravity theory, the metric of spacetime is given by [1,2,3,4] 1 : ĝµν = g µν + B∂ µ φ∂ ν φ,…”

Cosmology with Varying Constants from a Thermodynamic Viewpoint

“…For a detailed review, see [18][19][20]. There are different approaches to studying the variation of fundamental constants in cosmology [21][22][23][24][25][26][27][28][29]. In this report, we briefly summarize the approach given by us in [29] to study the variation of fundamental constants.…”