Gravitational Waves Induced by Non-Gaussian Scalar Perturbations

Abstract It is well known that primordial black hole (PBH) can be generated in inflation process of the early universe, especially when the inflaton field has some non-trivial features that could break the slow-roll condition. In this paper, we investigate a toy model of inflation with bumpy potential, which has one or several bumps. We found that potential with multi-bump can give rise to power spectra with multi peaks in small-scale region, which can in turn predict the generation of primordial black holes in various mass ranges. We also consider the two possibilities of PBH formation by spherical collapse and elliptical collapse. And discusses the scalar-induced gravitational waves (SIGWs) generated by the second-order scalar perturbations.

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SPECTRUM OF GRAVITATIONAL WAVES IN KREIN SPACE QUANTIZATION

Modern Physics Letters A ◽

10.1142/s021773231103708x ◽

2011 ◽

Vol 26 (36) ◽

pp. 2697-2702 ◽

Cited By ~ 5

Author(s):

M. MOHSENZADEH ◽

A. SOJASI ◽

E. YUSOFI

Keyword(s):

Gravitational Waves ◽

Krein Space ◽

Slow Roll ◽

Primordial Power Spectrum ◽

Alternative Approach ◽

Special Cases ◽

Kreĭn Space ◽

Field Quantization ◽

Krein Space Quantization ◽

Scalar Perturbations

The main goal of this paper is to derive the primordial power spectrum for the scalar perturbations generated as a result of quantum fluctuations during an inflationary period by an alternative approach of field quantization.1–3 Formulas are derived for the gravitational waves, special cases of which include power law inflation and inflation in the slow roll approximation, in Krein space quantization.

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The holographic spacetime model of cosmology

International Journal of Modern Physics D ◽

10.1142/s0218271818460057 ◽

2018 ◽

Vol 27 (14) ◽

pp. 1846005 ◽

Cited By ~ 2

Author(s):

Tom Banks ◽

W. Fischler

Keyword(s):

Dark Matter ◽

Gravitational Waves ◽

Structure Formation ◽

Big Bang ◽

Baryon Asymmetry ◽

Gaussian Fluctuations ◽

Primordial Gravitational Waves ◽

Conventional Models ◽

Non Gaussian ◽

The Big Bang

This essay outlines the Holographic Spacetime (HST) theory of cosmology and its relation to conventional theories of inflation. The predictions of the theory are compatible with observations, and one must hope for data on primordial gravitational waves or non-Gaussian fluctuations to distinguish it from conventional models. The model predicts an early era of structure formation, prior to the Big Bang. Understanding the fate of those structures requires complicated simulations that have not yet been done. The result of those calculations might falsify the model, or might provide a very economical framework for explaining dark matter and the generation of the baryon asymmetry.

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