Results 31 to 40 of about 180,985 (262)
Beyond Standard Inflationary Cosmology [PDF]
Beyond Spacetime, 2018 The inflationary scenario is not the only paradigm of early universe cosmology which is consistent with current observations. General criteria will be presented which any successful early universe model must satisfy.
R. Brandenberger
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Gravitational Fluctuations as an Alternative to Inflation
Universe, 2019 The ability to reproduce the observed matter power spectrum P ( k ) to high accuracy is often considered as a triumph of inflation. In this work, we explore an alternative explanation for the power spectrum based on nonperturbative quantum field ...
Herbert W. Hamber
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European Physical Journal C: Particles and Fields, 2021 We propose an extension of the scalaron-Higgs model by a non-minimal coupling of the Standard Model Higgs boson to the quadratic Ricci scalar resulting in a Higgs-dependent scalaron mass.
Anirudh Gundhi, Christian F. Steinwachs
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Inflationary Cosmology in Modified Gravity Theories [PDF]
Symmetry, 2015 We review inflationary cosmology in modified gravity such as R2 gravity with its extensions in order to generalize the Starobinsky inflation model. In particular, we explore inflation realized by three kinds of effects: modification of gravity, the ...
K. Bamba, S. Odintsov
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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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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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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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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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Inflationary cosmology in unimodular $F(T)$ gravity [PDF]
, 2016 We investigate the inflationary realization in the context of unimodular $F(T)$ gravity, which is based on the $F(T)$ modification of teleparallel gravity, in which one imposes the unimodular condition through the use of Lagrange multipliers.
K. Bamba, S. Odintsov, E. Saridakis
semanticscholar +1 more source
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.
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