Discrete Newtonian cosmology: perturbations [PDF]
Classical and Quantum Gravity, 2015 In a previous paper [arXiv:1308.1852] we showed how a finite system of discrete particles interacting with each other via Newtonian gravitational attraction would lead to precisely the same dynamical equations for homothetic motion as in the case of the pressure-free Friedmann-Lema tre-Robertson-Walker cosmological models of General Relativity Theory,
Ellis, George F. R., Gibbons, Gary W.
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Cosmological Perturbations in Double Field Theory
Journal of High Energy Physics, 2023 We explore perturbative double field theory about time-dependent (cosmological) backgrounds to cubic order. To this order the theory is consistent in a weakly constrained sense, so that for a toroidal geometry it encodes both momentum and genuine winding
Olaf Hohm, Allison F. Pinto
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The Osmium Isotope Signature of Phanerozoic Large Igneous Provinces
Geophysical Monograph Series, Page 229-246., 2021 Exploring the links between Large Igneous Provinces and dramatic environmental impact
An emerging consensus suggests that Large Igneous Provinces (LIPs) and Silicic LIPs (SLIPs) are a significant driver of dramatic global environmental and biological changes, including mass extinctions.
Alexander J. Dickson +2 more
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Braneworld cosmological perturbations in teleparallel gravity
Physics Letters B, 2015 In this paper we find the fully gauge invariant cosmological perturbation equations in braneworld teleparallel gravity. In this theory, perturbations are the result of small fluctuations in the pentad field. We derive the gauge invariant 'potentials' for
A. Behboodi, K. Nozari
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Configurational entropy and instability of tachyonic braneworld
Physics Letters B, 2020 We consider tachyonic braneworld with a bulk cosmological constant and investigate a configurational entropy of various magnitudes of scale factor. It is found that for a bulk negative/zero cosmological constant, the configurational entropy has a global ...
Chong Oh Lee
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COSMOLOGICAL PERTURBATIONS IN RENORMALIZATION GROUP DERIVED COSMOLOGIES [PDF]
International Journal of Modern Physics D, 2004 A linear cosmological perturbation theory of an almost homogeneous and isotropic perfect fluid Universe with dynamically evolving Newton constant G and cosmological constant Λ is presented. A gauge invariant formalism is developed by means of the covariant approach, and the acoustic propagation equations governing the evolution of the comoving ...
Bonanno, A., Reuter, M.
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On the Back Reaction Problem for Gravitational Perturbations [PDF]
, 1996 We derive the effective energy-momentum tensor for cosmological perturbations and prove its gauge-invariance. The result is applied to study the influence of perturbations on the behaviour of the Friedmann background in inflationary Universe scenarios ...
A. A. Starobinsky +17 more
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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
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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 on local systems [PDF]
, 2006 We study the effect of cosmological expansion on orbits--galactic, planetary, or atomic--subject to an inverse-square force law. We obtain the laws of motion for gravitational or electrical interactions from general relativity--in particular, we find the
A. Krasiński +15 more
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