Results 31 to 40 of about 708 (181)
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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Physics Letters B, 2022 In Chain Inflation the universe tunnels along a series of false vacua of ever-decreasing energy. The main goal of this paper is to embed Chain Inflation in high energy fundamental physics.
Katherine Freese +2 more
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Cosmological parameters in noncommutative inflation [PDF]
Physics Letters B, 2004 We investigate how the uncertainty of noncommutative spacetime could explain the WMAP data. For this purpose, the spectrum is divided into the IR and UV region. We introduce a noncommutative parameter of $γ_0$ in the IR region and a noncommutative parameter of $μ_0$ in the UV region. We calculate cosmological parameters using the slow-roll expansion in
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Effect of inflation on anisotropic cosmologies [PDF]
Physical Review D, 1986 We study the effects of anisotropic cosmologies on inflation. By properly formulating the field equations it is possible to show that any model that undergoes sufficient inflation will become isotropic on scales greater than the horizon today. Furthermore, we shall show that it takes a very long time for anisotropies to become visible in the observable
, Jensen, , Stein-Schabes
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Towards geometric inflation: The cubic case
Physics Letters B, 2020 We present an up to cubic curvature correction to General Relativity with the following features: (i) its vacuum spectrum solely consists of a graviton, (ii) it possesses well-behaved black hole solutions which coincide with those of Einsteinian cubic ...
Gustavo Arciniega +2 more
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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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Towards a cosmological dual to inflation
Physical Review D, 2011 We derive all single-field cosmologies with unit sound speed that generate scale invariant curvature perturbations on a dynamical attractor background. We identify three distinct phases: slow-roll inflation; a slowly contracting adiabatic ekpyrotic phase, described by a rapidly-varying equation of state; and a novel adiabatic ekpyrotic phase on a ...
Khoury, Justin, Miller, Godfrey E.J.
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A new mechanism for freezing extra dimensions with higher-order curvature terms
Physics Letters B, 2020 We construct a model of higher dimensional cosmology in which extra dimensions are frozen by virtue of the cubic-order Lovelock gravity throughout the cosmic history from inflation to the present with radiation and matter-dominated regimes in between.
Hiroaki W.H. Tahara +2 more
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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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Stationarity of inflation and predictions of quantum cosmology [PDF]
Physical Review D, 1995 We describe several different regimes which are possible in inflationary cosmology. The simplest one is inflation without self-reproduction of the universe. In this scenario the universe is not stationary. The second regime, which exists in a broad class of inflationary models, is eternal inflation with the self-reproduction of inflationary domains. In
Garcia-Bellido, Juan, Linde, Andrei
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