Results 11 to 20 of about 6,704,491 (163)
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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Group Field Theory Condensate Cosmology: An Appetizer [PDF]
Universe, 2019 This contribution is an appetizer to the relatively young and fast-evolving approach to quantum cosmology based on group field theory condensate states. We summarize the main assumptions and pillars of this approach which has revealed new perspectives on
A. G. A. Pithis, M. Sakellariadou
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Reheating in Inflationary Cosmology: Theory and Applications [PDF]
, 2010 Reheating is an important part of inflationary cosmology. It describes the production of Standard Model particles after the phase of accelerated expansion.
R. Allahverdi +3 more
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The CAMELS Project: Cosmology and Astrophysics with Machine-learning Simulations [PDF]
Astrophysical Journal, 2020 We present the Cosmology and Astrophysics with MachinE Learning Simulations (CAMELS) project. CAMELS is a suite of 4233 cosmological simulations of 25h−1Mpc3 volume each: 2184 state-of-the-art (magneto)hydrodynamic simulations run with the AREPO and ...
F. Villaescusa-Navarro +21 more
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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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Inflationary cosmology: from theory to observations [PDF]
Revista mexicana de física E, 2018 The main aim of this paper is to provide a qualitative introduction to the cosmological inflation theory and its relationship with current cosmological observations.
J. Alberto Vazquez Gonzalez +2 more
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The effective field theory of nonsingular cosmology: II [PDF]
The European Physical Journal C, 2017 Based on the effective field theory (EFT) of cosmological perturbations, we explicitly clarify the pathology in nonsingular cubic Galileon models and show how to cure it in EFT with new insights into this issue.
Yong Cai +3 more
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The Effective Field Theory of nonsingular cosmology [PDF]
Journal of High Energy Physics, 2016 In this paper, we explore the nonsingular cosmology within the framework of the Effective Field Theory (EFT) of cosmological perturbations. Due to the recently proved no-go theorem, any nonsingular cosmological models based on the cubic Galileon suffer ...
Yong Cai +4 more
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Effective loop quantum cosmology as a higher-derivative scalar-tensor theory [PDF]
, 2017 Recently, Chamseddine and Mukhanov introduced a higher-derivative scalar-tensor theory which leads to a modified Friedmann equation allowing for bouncing solutions.
D. Langlois +3 more
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