Results 21 to 30 of about 400,960 (288)
GRAMSES: a new route to general relativistic N-body simulations in cosmology. Part I. Methodology and code description [PDF]
Journal of Cosmology and Astroparticle Physics, 2019 We present GRAMSES, a new pipeline for nonlinear cosmological N-body simulations in General Relativity (GR). This code adopts the Arnowitt-Deser-Misner (ADM) formalism of GR, with constant mean curvature and minimum distortion gauge fixings, which ...
C. Barrera-Hinojosa, Baojiu Li
semanticscholar +1 more source
Lagrangian theory of structure formation in relativistic cosmology II: average properties of a generic evolution model [PDF]
, 2013 Kinematical and dynamical properties of a generic inhomogeneous cosmological model, spatially averaged with respect to free-falling (generalized fundamental) observers, are investigated for the matter model "irrotational dust.'' Paraphrasing a previous ...
T. Buchert, Charly Nayet, A. Wiegand
semanticscholar +1 more source
On the covariance of scalar averaging and backreaction in relativistic inhomogeneous cosmology [PDF]
Classical and quantum gravity, 2018 We introduce a generalization of the 4-dimensional averaging window function of Gasperini et al (2010 J. Cosmol. Astropart. Phys. JCAP02(2010)009) that may prove useful for a number of applications.
A. Heinesen, P. Mourier, T. Buchert
semanticscholar +1 more source
Type V singularities with inhomogeneous equations of state
Physics Letters B, 2022 Interest in cosmological singularities has remarkably grown in recent times, particularly on future singularities with the discovery of late-time acceleration of the universe and dark energy.
Oem Trivedi
doaj +1 more source
Relativistic Fractional-Dimension Gravity
Universe, 2021 This paper presents a relativistic version of Newtonian Fractional-Dimension Gravity (NFDG), an alternative gravitational model recently introduced and based on the theory of fractional-dimension spaces.
Gabriele U. Varieschi
doaj +1 more source
Newtonian and relativistic cosmologies
Physical Review D, 2012 Cosmological N-body simulations are now being performed using Newtonian gravity on scales larger than the Hubble radius. It is well known that a uniformly expanding, homogeneous ball of dust in Newtonian gravity satisfies the same equations as arise in relativistic FLRW cosmology, and it also is known that a correspondence between Newtonian and ...
Green, Stephen R., Wald, Robert M.
openaire +3 more sources
Cosmological analogies, Lagrangians, and symmetries for convective–radiative heat transfer
European Physical Journal C: Particles and Fields, 2020 A formal analogy between the Friedmann equation of relativistic cosmology and models of convective–radiative cooling/heating of a body (including Newton’s, Dulong–Petit’s, Newton–Stefan’s laws, and a generalization) is discussed.
Valerio Faraoni +2 more
doaj +1 more source
An Exact quantification of backreaction in relativistic cosmology [PDF]
, 2012 An important open question in cosmology is the degree to which the Friedmann-Lema\^{\i}tre-Robertson-Walker (FLRW) solutions of Einstein's equations are able to model the large-scale behavior of the locally inhomogeneous observable universe.
T. Clifton, K. Rosquist, R. Tavakol
semanticscholar +1 more source
CHARLES SANDERS PEIRCE AND THE PLACE OF CHAOS IN THE NEW WORLD ORDER [PDF]
Filozofia i NaukaThis article examines the main ideas of the metaphysics of the prominent American logician and philosopher Charles Sanders Peirce. It is shown that a significant part of his „scientific metaphysics” is evolutionary cosmology, characterized, in particular,
Volodymyr Ratnikov
doaj +1 more source
Correspondence between dark energy quantum cosmology and Maxwell equations
European Physical Journal C: Particles and Fields, 2019 A Friedmann–Robertson–Walker cosmology with dark energy can be modelled using a quintessence field. That system is equivalent to a relativistic particle moving on a two-dimensional conformal spacetime.
Felipe A. Asenjo, Sergio A. Hojman
doaj +1 more source