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The magnification of distant sources by mass clumps at lower ($z \leq 1$) redshifts is calculated analytically. The clumps are initially assumed to be galaxy group isothermal spheres with properties inferred from an extensive survey. The…

Astrophysics · Physics 2007-05-23 Richard Lieu , Jonathan P. D. Mittaz

Present day cosmic microwave background (CMB) studies require more accurate removal of Galactic foreground emission. In this paper, we consider a way of filtering out the diffuse Galactic fluctuations on the basis of their statistical…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Jungyeon Cho , A. Lazarian

Quantum fluctuations in spacetime can, in some cases, lead to distortion in astronomical images of faraway objects. In particular, a stochastic model of quantum gravity predicts an accumulated fluctuation in the path length $\Delta L$ with…

General Relativity and Quantum Cosmology · Physics 2024-05-24 Vincent S. H. Lee , Kathryn M. Zurek , Yanbei Chen

The standard model of large scale structure is considered, in which the structure originates as a Gaussian adiabatic density perturbation with a nearly scale invariant spectrum. The basic theoretical tool of cosmological perturbation theory…

Astrophysics · Physics 2007-05-23 David H Lyth , Andrew R Liddle

Recent deep X-ray surveys combined with spectroscopic identification of the sources have allowed the determination of the rest-frame 2-8 keV luminosity as a function of redshift. In addition, an analysis of the HEAO1 A2 2-10 keV full-sky…

Astrophysics · Physics 2009-11-10 Stephen Boughn , Robert Crittenden

We study a hard sphere gas at equilibrium, and prove that in the low density limit, the fluctuations converge to a Gaussian process governed by the fluctuating Boltzmann equation. This result holds for arbitrarily long times. The method of…

Analysis of PDEs · Mathematics 2022-01-13 Thierry Bodineau , Isabelle Gallagher , Laure Saint-Raymond , Sergio Simonella

A generalization of the random fluid hydrodynamic fluctuation theory due to Landau and Lifshitz is applied to describe cosmological fluctuations in systems with radiation and scalar fields. The viscous pressures, parametrized in terms of…

Cosmology and Nongalactic Astrophysics · Physics 2016-01-14 Mar Bastero-Gil , Arjun Berera , Ian G. Moss , Rudnei O. Ramos

The fluctuations of the cosmic microwave background (CMB) are investigated for a small open universe, i.e., one which is periodically composed of a small fundamental cell. The evolution of initial metric perturbations is computed using the…

Astrophysics · Physics 2009-10-31 Ralf Aurich

We aim to present a tutorial on the detection, parameter estimation and statistical analysis of compact sources (far galaxies, galaxy clusters and Galactic dense emission regions) in cosmic microwave background observations. The topic is of…

Instrumentation and Methods for Astrophysics · Physics 2011-01-05 D. Herranz , P. Vielva

Most old distant radio galaxies should be extended X-ray sources due to inverse Compton scattering of Cosmic Microwave Background (CMB) photons. Such sources can be an important component in X-ray surveys for high redshift clusters, due to…

Astrophysics · Physics 2016-08-30 A. Celotti , A. C. Fabian

Quantum fluctuations can endow spacetime with a foamy structure. In this review article we discuss our various proposals to observationally constrain models of spacetime foam. One way is to examine if the light wave-front from a distant…

General Relativity and Quantum Cosmology · Physics 2022-07-12 Y. Jack Ng , Eric S. Perlman

Weak lensing is the distortion (polarization) of images of distant objects, such as high redshift galaxies, by gravitational fields in the limit where the distortion is small. Gravitational potential fluctuations due to large scale…

Astrophysics · Physics 2015-06-24 Jens Verner Villumsen

Low-mass X-ray binaries, recycled pulsars, cataclysmic variables and magnetically active binaries are observed as X-ray sources in globular clusters. We discuss the classification of these systems, and find that some presumed active…

Astrophysics · Physics 2009-11-13 Frank Verbunt , Dave Pooley , Cees Bassa

A model to explain variable gamma-ray sources with high-mass microblazars is described. Inverse Compton interactions between the jet of a microquasar and the UV-photon field of the stellar companion can produce high-energy gamma-rays. The…

Astrophysics · Physics 2007-05-23 M. M. Kaufman Bernado , G. E. Romero , I. F. Mirabel

( to appear in: Proceedings of the Nishonomiya Yukawa Memorial Symposium Edited by M. Sasaki) There are several models for generating fluctuations in an open universe that are compatible with the microwave background fluctuations detected…

Astrophysics · Physics 2009-09-25 David N. Spergel , Ue-Li Pen , Marc Kamionkowski , Naoshi Sugiyama

We discuss cosmological inference from galaxy surveys at low and high redshifts. Studies of optical and IRAS redshift surveys with median redshift ${\bar z} \sim 0.02$ yield measurements of the density parameter $\Omega$ and the…

Astrophysics · Physics 2007-05-23 Ofer Lahav

A new field theory formulation is presented for the analysis of the CMB power spectrum distribution in the cosmology. The background-field formalism is fully used. Stimulated by the recent idea of the {\it emergent} gravity, the…

High Energy Physics - Theory · Physics 2013-10-22 Shoichi Ichinose

Extra-galactic sources of photons have been used to constrain space-time quantum fluctuations in the Universe. In these proposals, the fundamental "fuzziness" of distance caused by space-time quantum fluctuations has been directly…

High Energy Astrophysical Phenomena · Physics 2015-06-24 Yanbei Chen , Linqing Wen , Yiqiu Ma

The Milky Way can act as a large-scale weak gravitational lens of the cosmic microwave background (CMB). We study this effect using a photon ray-tracing code and a Galactic mass distribution with disk, bulge and halo components. For an…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-22 Benjamin Czaja , Benjamin C. Bromley

An approach is suggested for treating multiscale fluctuations in macromolecular systems. The emphasis is on the statistical properties of such fluctuations. The approach is illustrated by a macromolecular system with mesoscopic fluctuations…

Chemical Physics · Physics 2012-08-07 V. I. Yukalov , E. P. Yukalova