Results 11 to 20 of about 2,315 (187)
String theory and cosmology [PDF]
General Relativity and Gravitation, 1996 We discuss the main cosmological implications of considering string-loop effects and a potential for the dilaton in the lowest order string effective action. Our framework is based on the effective model arising from regarding homogeneous and isotropic dilaton, metric and Yang-Mills field configurations.
Bento, M. C., Bertolami, O.
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Inhomogeneous M-theory cosmologies [PDF]
Journal of Mathematical Physics, 2002 We study a class of inhomogeneous and anisotropic G2 string cosmological models. In the case of separable G2 models we show that the governing equations reduce to a system of ordinary differential equations. We focus on a class of separable G2 M-theory cosmological models, and study their qualitative behavior (a class of models with time-reversed ...
Coley, Alan A., van den Hoogen, R. J.
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Cosmological theory without singularities [PDF]
Physical Review D, 1993 A theory of gravitation is constructed in which all homogeneous and isotropic solutions are nonsingular, and in which all curvature invariants are bounded. All solutions for which curvature invariants approach their limiting values approach de Sitter space. The action for this theory is obtained by a higher derivative modification of Einstein's theory.
Brandenberger, R. +2 more
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SSRN Electronic Journal, 2023 In cosmological special relativity theory, we study Maxwell equations, electromagnetic wave equations and functions. In the cosmological special theory of relativity, we study energy?momentum relations, the Klein-Gordon equation and wave functions. If we solve the Klein?Gordon equation, we obtain the Yukawa potential in the cosmological inertial frame.
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Axions: Theory and Cosmological Role [PDF]
Annual Review of Nuclear and Particle Science, 2013 We review recent developments in axion cosmology. Topics include axion cold dark matter, axions from topological defects, axion isocurvature perturbation and its non-Gaussianity, and axino/saxion cosmology in a supersymmetric axion model.
Kawasaki, Masahiro, Nakayama, Kazunori
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Cosmological Relativity: A New Theory of Cosmology
, 2000 A general-relativistic theory of cosmology, the dynamical variables of which are those of Hubble's, namely distances and redshifts, is presented. The theory describes the universe as having a three-phase evolution with a decelerating expansion followed by a constant and an accelerating expansion, and it predicts that the universe is now in the latter ...
Behar, Silvia, Carmeli, Moshe
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Quasidilaton: Theory and cosmology
Physical Review D, 2013 General Relativity (GR), with or without matter fields, admits a natural extension to a scale invariant theory that requires a dilaton. Here we show that the recently formulated massive GR, minimally coupled to matter, possesses a new global symmetry related to scaling of the reference coordinates w.r.t. the physical ones.
D'Amico, Guido +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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Theory of cosmological perturbations with cuscuton [PDF]
Journal of Cosmology and Astroparticle Physics, 2017 This paper presents the first derivation of the quadratic action for curvature perturbations, $ΞΆ$, within the framework of cuscuton gravity. We study the scalar cosmological perturbations sourced by a canonical single scalar field in the presence of cuscuton field.
Boruah, Supranta S. +2 more
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Physics of the Dark Universev2, Appendix added with some more details on the teleodynamic field, 58 pages with no ...
Oem Trivedi, Venkat Venkatasubramanian
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