Results 11 to 20 of about 42,432 (292)
De Sitter Solutions in Einstein–Gauss–Bonnet Gravity
Universe, 2021 De Sitter solutions play an important role in cosmology because the knowledge of unstable de Sitter solutions can be useful to describe inflation, whereas stable de Sitter solutions are often used in models of late-time acceleration of the Universe.
Sergey Vernov, Ekaterina Pozdeeva
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Nonperturbative quantum de Sitter universe [PDF]
Physical Review D, 2008 Article unchanged.
Ambjørn, Jan +3 more
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Quantum field theory in a de-Sitter universe transiting to the radiation stage
Journal of High Energy Physics, 2022 We study some physical aspects of quantum field theory in a two stage universe starting from the inflationary de Sitter and transiting into the radiation dominated stage.
Juan R. Salazar, Sujoy K. Modak
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THE SELF-ORGANIZED DE SITTER UNIVERSE [PDF]
International Journal of Modern Physics D, 2008 We propose a theory of quantum gravity which formulates the quantum theory as a nonperturbative path integral, where each space–time history appears with the weight exp (iS EH ), with S EH the Einstein–Hilbert action of the corresponding causal geometry. The path integral is diffeomorphism-invariant (only geometries appear) and background-independent.
Ambjørn, Jan, Jurkiewicz, J., Loll, R.
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Classification of curves on de Sitter plane
Pracì Mìžnarodnogo Geometričnogo Centru, 2020 In 1917, de Sitter used the modified Einstein equation and proposed a model of the Universe without physical matter, but with a cosmological constant. De Sitter geometry, as well as Minkowski geometry, is maximally symmetrical.
Irina Streltsova
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Gravitationally induced adiabatic particle production: from big bang to de Sitter [PDF]
, 2016 In the background of a flat homogeneous and isotropic space–time, we consider a scenario of the Universe driven by the gravitationally induced 'adiabatic' particle production with constant creation rate.
Haro Cases, Jaume
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De Sitter scattering amplitudes in the Born approximation
SciPost Physics, 2022 We present a covariant framework to compute scattering amplitudes and potentials in a de Sitter background. In this setting, we compute the potential of a graviton-mediated scattering process involving two very massive scalars at tree level. Although the
Renata Ferrero, Chris Ripken
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De Sitter universe in nonlocal gravity [PDF]
Physical Review D, 2012 20 pages, version to appear in Phys.
Elizalde, E. +2 more
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MeV Dark Energy Emission from a De Sitter Universe
Universe, 2023 The evolution of a de Sitter Universe is the basis for both the accelerated Universe and the late-stationary Universe. So, how do we differentiate between both universes?
Yasmín B. Alcántara-Pérez +3 more
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Discrete symmetries of Dirac’s theory in the de Sitter manifold
European Physical Journal C: Particles and Fields, 2023 The discrete symmetries of Dirac’s free field on the de Sitter manifold are studied, taking into account that this has two portions that can play the role of physical space-times, namely an expanding and a collapsing universe.
Ion I. Cotăescu, Ion Cotăescu
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