Results 31 to 40 of about 6,704,491 (163)
Cosmological solutions in string theories [PDF]
Physical Review D, 1997 Latex, 21 pages, a reference ...
Lu, H. +3 more
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Value of the Cosmological Constant in the Cosmological Relativity Theory
International Journal of Theoretical Physics, 2002 It is shown that the cosmological relativity theory prdicts the value Lambda = 1.934 x 10^-35 s^-2 for the cosmological constant. This value of Lambda is in exellent agreement with the measurements recently obtained by the High-Z Supernova Team and the Supernova Cosmology Project.
Carmeli, Moshe, Kuzmenko, Tanya
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Comments on wormholes, ensembles, and cosmology [PDF]
Journal of High Energy Physics, 2020 Certain closed-universe big-bang/big-crunch cosmological spacetimes may be obtained by analytic continuation from asymptotically AdS Euclidean wormholes, as emphasized by Maldacena and Maoz.
Mark Van Raamsdonk
semanticscholar +1 more source
Cosmology in bimetric theory with an effective composite coupling to matter [PDF]
, 2015 We study the cosmology of bimetric theory with a composite matter coupling. We find two possible branches of background evolution. We investigate the question of stability of cosmological perturbations.
A. Gümrükçüoğlu +4 more
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The Landscape, the Swampland and the Era of Precision Cosmology [PDF]
Fortschritte der Physik, 2018 We review the advanced version of the KKLT construction and pure d=4 de Sitter supergravity, involving a nilpotent multiplet, with regard to various conjectures that de Sitter state cannot exist in string theory.
Yashar Akrami +3 more
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Cosmology and gravitational waves in consistent D→ 4 Einstein-Gauss-Bonnet gravity [PDF]
Journal of Cosmology and Astroparticle Physics, 2020 In a very recent paper [1], we have proposed a novel 4-dimensional gravitational theory with two dynamical degrees of freedom, which serves as a consistent realization of D→4 Einstein-Gauss-Bonnet gravity with the rescaled Gauss-Bonnet coupling constant ̃
K. Aoki, M. Gorji, S. Mukohyama
semanticscholar +1 more source
Cosmology in symmetric teleparallel gravity and its dynamical system [PDF]
The European Physical Journal C, 2019 We explore an extension of the symmetric teleparallel gravity denoted the f(Q) theory, by considering a function of the nonmetricity invariant Q as the gravitational Lagrangian.
Jianbo Lu, Xin Zhao, G. Chee
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Hamiltonian cosmological perturbation theory [PDF]
Physics Letters B, 2006 The Hamiltonian approach to cosmological perturbations in general relativity in finite space-time is developed, where a cosmological scale factor is identified with spatial averaging the metric determinant logarithm. This identification preserves the number of variables and leads to a cosmological perturbation theory with the scalar potential ...
Barbashov, B. M. +3 more
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An embedding of loop quantum cosmology in ( b , v ) variables into a full theory context [PDF]
, 2015 Loop quantum cosmology in (b, v) variables, which is governed by a unit step size difference equation, is embedded into a full theory context based on similar variables.
N. Bodendorfer
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Dark energy cosmology: the equivalent description via different theoretical models and cosmography tests [PDF]
, 2012 We review different dark energy cosmologies. In particular, we present the ΛCDM cosmology, Little Rip and Pseudo-Rip universes, the phantom and quintessence cosmologies with Type I, II, III and IV finite-time future singularities and non-singular dark ...
K. Bamba +3 more
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