Results 31 to 40 of about 32,779 (246)
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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Gravitational Fluctuations as an Alternative to Inflation II. CMB Angular Power Spectrum
Universe, 2019 Power spectra always play an important role in the theory of inflation. In particular, the ability to reproduce the galaxy matter power spectrum P ( k ) and the CMB temperature angular power spectrum C l ’s to high accuracy is often ...
Herbert W. Hamber, Lu Heng Sunny Yu
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Bottom-up reconstruction of non-singular bounce in F(R) gravity from observational indices
Nuclear Physics B, 2020 We apply the bottom-up reconstruction technique in the context of bouncing cosmology in F(R) gravity, where the starting point is a suitable ansatz of observable quantity (like spectral index or tensor to scalar ratio) rather than a priori form of Hubble
S.D. Odintsov +2 more
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Entropic Inflation in Presence of Scalar Field
Universe, 2023 In spirit of the recently proposed four-parameter generalized entropy of apparent horizon, we investigate inflationary cosmology where the matter field inside of the horizon is dominated by a scalar field with a power law potential (i.e., the form of ϕn ...
Sergei D. Odintsov +2 more
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Are we seeing the beginnings of Inflation? [PDF]
, 2009 Phantom Cosmology provides an unique opportunity to "connect" the phantom driven (low en- ergy meV scale) dark energy phase to the (high energy GUT scale) inflationary era. This is possible because the energy density increases in phantom cosmology.
Cosmin Ilie +6 more
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5D generalized inflationary cosmology [PDF]
General Relativity and Gravitation, 1995 We consider 5D Kaluza-Klein type cosmological model with the fifth coordinate being a generalization of the invariant ``historical'' time $ $ of the covariant theory of Horwitz and Piron. We distinguish between vacuum-, off-shell matter-, and on-shell matter-dominated eras as the solutions of the corresponding 5D gravitational field equations, and ...
Burakovsky, L., Horwitz, L. P.
openaire +3 more sources
European Physical Journal C: Particles and Fields, 2023 We demonstrate a spontaneous tendency of quantum wave packets to become quasi-classical, providing a classical limit for the Universe dynamics. However, this limit is not maintained in the future (after a critical value of the relational time) and a ...
Mariaveronica De Angelis +1 more
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Looking inside the Swampland from Warm Inflation: Dissipative Effects in De Sitter Expansion
Universe, 2023 This paper reviews the theoretical and phenomenological implications of the swampland conjectures from the perspective of inflationary cosmology, focusing on warm inflation.
Arjun Berera, Jaime Calderón-Figueroa
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On the initial singularity and extendibility of flat quasi-de Sitter spacetimes
Journal of High Energy Physics, 2023 Inflationary spacetimes have been argued to be past geodesically incomplete in many situations. However, whether the geodesic incompleteness implies the existence of an initial spacetime curvature singularity or whether the spacetime may be extended ...
Ghazal Geshnizjani +2 more
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