Results 41 to 50 of about 242,934 (254)
Novel vacuum conditions in inflationary collapse models
Physics Letters B, 2017 Within the framework of inflationary models that incorporate a spontaneous reduction of the wave function for the emergence of the seeds of cosmic structure, we study the effects on the primordial scalar power spectrum by choosing a novel initial quantum
Gabriel R. Bengochea, Gabriel León
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Constant-roll inflation in brane induced gravity cosmology
European Physical Journal C: Particles and Fields, 2022 In this article we study a constant-roll inflationary model in the context of the DGP brane-world cosmology caused by a quintessence scalar field. We determine an analytical solution for the Friedman equation coupled to the equation of motion of the ...
A. Ravanpak, G. F. Fadakar
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Universe, 2020 We investigate the ability of the exponential power-law inflation to be a phenomenologically correct model of the early universe. We study General Relativity (GR) scalar cosmology equations in Ivanov–Salopek–Bond (or Hamilton–Jacobi like) representation ...
Igor Fomin, Sergey Chervon
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Cosmology analogues in optical systems [PDF]
EPJ Web of Conferences, 2020 We discuss the possibility of exploiting polariton-exciton physics as an analogue experimental tool to study challenging ideas and existing problems arising in the context of gravity theory and theoretical cosmology.
Howard Eric
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Back Reaction and Graceful Exit in String Inflationary Cosmology [PDF]
, 1996 Classical string cosmology consists of two branches related to each other by scale-factor duality: a super-inflation branch and a Friedmann-Robertson-Walker (FRW) branch. Curvature and string coupling singularity separates the two branches, hence posing `
A. Albrecht +21 more
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A more accurate analytic calculation of the spectrum of cosmological perturbations produced during inflation [PDF]
Phys.Lett.B302:171-175,1993, 1993 Formulae are derived for the spectra of scalar curvature perturbations and gravitational waves produced during inflation, special cases of which include power law inflation, natural inflation in the small angle approximation and inflation in the slow roll approximation.
arxiv +1 more source
Inflation and Cosmological Perturbations [PDF]
, 2010 56 pages, 5 figures; Lectures given at the Second TRR33 Winter School on cosmology, Passo del Tonale (Italy), December ...
openaire +6 more sources
Inflation with a negative cosmological constant [PDF]
Physical Review D, 2009 We find a unique way of realizing inflation through cyclic phases in an universe with negative vacuum energy. According to the second law of thermodynamics entropy monotonically increases from cycle to cycle, typically by a constant factor. This means that the scale factor at the same energy density in consecutive cycles also increases by a constant ...
Anupam Mazumdar +2 more
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Nearly Forgotten Cosmological Concept of E. B. Gliner
Universe, 2023 E. B. Gliner started his scientific career in 1963 at the age of 40. In 1965, when the existence of the cosmological constant λ seemed unnecessary to most cosmologists, he renewed interest in the problem by emphasizing a material interpretation of de ...
Dmitry Yakovlev, Alexander Kaminker
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, 1995 An exploratory study of the cosmology of moduli in string theory. Moduli are argued to be natural inflaton fields and lead to a robust inflationary cosmology in which inflation takes place at the top of domain walls. The amplitude of microwave background
A. Albrecht +54 more
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