Results 31 to 40 of about 299,841 (224)
Primordial black holes in non-linear perturbation theory [PDF]
, 2009 PhDThe thesis begins with a study of the origin of non-linear cosmological fluctuations. In particular, a class of models of multiple field inflation are considered, with specific reference to those cases in which the non-Gaussian correlation functions
Hidalgo-Cuellar, Juan Carlos
core +4 more sources
Disformal transformation of cosmological perturbations
Physics Letters B, 2014 We investigate the gauge-invariant cosmological perturbations in the gravity and matter frames in the general scalar–tensor theory where two frames are related by the disformal transformation.
Masato Minamitsuji
doaj +1 more source
Processing of cosmological perturbations in a cyclic cosmology [PDF]
Physical Review D, 2009 5 pages, 1 ...
openaire +2 more sources
Stabilizing homogeneous black strings in AdS
Journal of High Energy Physics, 2020 It is known that homogenous black strings in flat spacetime are unstable under long wavelength perturbations. Recently, by including scalar fields that depend on the extended coordinates only, homogenous black strings have been constructed in the ...
Adolfo Cisterna +2 more
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Cosmological perturbations and dynamical analysis for interacting quintessence
European Physical Journal C: Particles and Fields, 2019 We present the dynamical analysis for interacting quintessence, considering linear cosmological perturbations. Matter perturbations improve the background analysis and viable critical points describing the transition of the three cosmological eras are ...
Ricardo G. Landim
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COSMOLOGICAL PERTURBATIONS AND THE RUNNING COSMOLOGICAL CONSTANT MODEL [PDF]
International Journal of Modern Physics D, 2012 We study the matter density fluctuations in the running cosmological constant (RCC) model using linear perturbations in the longitudinal gauge. Using this observable, we calculate the growth rate of structures and the matter power spectrum, and compare these results to SDSS data and the available data for linear growth rate.
openaire +2 more sources
Cosmological perturbations at second order and recombination perturbed [PDF]
Journal of Cosmology and Astroparticle Physics, 2009 47 pages, 6 ...
Senatore, Leonardo +2 more
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COSMOLOGICAL PERTURBATIONS IN PRESENCE OF SCALAR FIELDS
Odessa Astronomical Publications, 2014 We investigate the role of the scalar field assuming its presence at late stages of the Universe evolution together with dust presented by a system of an arbitrary number of gravitating masses (galaxies, groups of galaxies and clusters of galaxies) and ...
A. Yu. Burgazli, M. Eingorn, A. Zhuk
doaj +1 more source
Cosmological perturbations engendered by discrete relativistic species
European Physical Journal C: Particles and Fields, 2023 Within the extension of the $$\varLambda $$ Λ CDM model, allowing for the presence of neutrinos or warm dark matter, we develop the analytical cosmological perturbation theory.
Maksym Brilenkov +2 more
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Quantum Gravity and Cosmological Density Perturbations
Galaxies, 2014 We explore the possible cosmological consequences of a running Newton’s constant, G(⎕), as suggested by the non-trivial ultraviolet fixed point scenario for Einstein gravity with a cosmological constant term.
Herbert W. Hamber, Reiko Toriumi
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