Results 21 to 30 of about 2,969 (164)
Effects of a Late Gravitational Transition on Gravitational Waves and Anticipated Constraints
Universe, 2023 We investigate the evolution of gravitational waves through discontinuous evolution (transition) of the Hubble expansion rate H(z) at a sudden cosmological singularity, which may be due to a transition of the value of the gravitational constant.
Evangelos Achilleas Paraskevas +1 more
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Anisotropic cosmological dynamics in f(T) gravity in the presence of a perfect fluid
European Physical Journal C: Particles and Fields, 2019 We consider the cosmological evolution of a flat anisotropic Universe in f(T) gravity in the presence of a perfect fluid. It is shown that the matter content of the Universe has a significant impact of the nature of a cosmological singularity in the ...
Maria A. Skugoreva, Alexey V. Toporensky
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The Astrophysical Journal Letters, 2023 We infer the evolution of the UV luminosities of galaxies in haloes of masses 10 ^10 –10 ^11 M _⊙ in the redshift range of z ∼ 9–16 from the recent JWST data.
Hamsa Padmanabhan, Abraham Loeb
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Cosmological evolution on self-tuned branes and the cosmological constant [PDF]
Journal of High Energy Physics, 2001 24 pages, JHEP ...
Brax, Ph., Davis, A. C.
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Black hole thermodynamics with dynamical lambda
Journal of High Energy Physics, 2017 We study evolution and thermodynamics of a slow-roll transition between early and late time de Sitter phases, both in the homogeneous case and in the presence of a black hole, in a scalar field model with a generic potential having both a maximum and a ...
Ruth Gregory +2 more
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Cosmological evolution of two-scalar fields cosmology in the Jordan frame
European Physical Journal C: Particles and Fields, 2020 In the present article we study the cosmological evolution of a two-scalar field gravitational theory defined in the Jordan frame. Specifically, we assume one of the scalar fields to be minimally coupled to gravity, while the second field which is the ...
Alex Giacomini +3 more
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Evolution of Nonlinear Cosmological Perturbations
Physical Review Letters, 2005 We define fully non-perturbative generalizations of the uniform density and comoving curvature perturbations, which are known, in the linear theory, to be conserved on sufficiently large scales for adiabatic perturbations. Our non-linear generalizations are defined geometrically, independently of any coordinate system.
Langlois, David, Vernizzi, F.
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Evolution of cosmological perturbations in nonsingular string cosmologies
Physical Review D, 2001 In a class of non-singular cosmologies derived from higher-order corrections to the low-energy bosonic string action, we derive evolution equations for the most general cosmological scalar, vector and tensor perturbations. In the large scale limit, the evolutions of both scalar and tensor perturbations are characterised by conserved quantities, the ...
Cartier, Cyril +2 more
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Cosmological evolution and hierarchical galaxy formation [PDF]
Monthly Notices of the Royal Astronomical Society, 1999 We provide a new multi-waveband compilation of the data describing the cosmological evolution of quasars, and discuss a model that attributes the evolution to variation in the rate of merging between dark halos in a hierarchical universe. We present a new Press-Schechter calculation of the expected merger rate and show that this can reproduce the ...
Percival, W, Miller, L
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Cosmological evolution of galaxies [PDF]
, 2013 I review the subject of the cosmological evolution of galaxies, including different aspects of growth in disk galaxies, by focussing on the angular momentum problem, mergers, and their by-products. I discuss the alternative to merger-driven growth -- cold accretion and related issues.
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