Cosmic microwave background anisotropy from nonlinear structures in accelerating universes
Abstract
We study the cosmic microwave background (CMB) anisotropy due to spherically symmetric nonlinear structures in flat universes with dust and a cosmological constant. By modeling a timeevolving spherical compensated void/lump by LemaitreTolmanBondi spacetimes, we numerically solve the null geodesic equations with the Einstein equations. We find that a nonlinear void redshifts the CMB photons that pass through it regardless of the distance to it. In contrast, a nonlinear lump blueshifts (or redshifts) the CMB photons if it is located near (or sufficiently far from) us. The present analysis comprehensively covers previous works based on a thinshell approximation and a linear/secondorder perturbation method and the effects of shell thickness and full nonlinearity. Our results indicate that, if quasilinear and large (> or approx.100 Mpc) voids/lumps would exist, they could be observed as cold or hot spots with temperature variance > or approx. 10{sup 5} K in the CMB sky.
 Authors:
 Department of Education, Yamagata University, Yamagata 9908560 (Japan)
 (Japan)
 Publication Date:
 OSTI Identifier:
 21250818
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physical Review. D, Particles Fields; Journal Volume: 78; Journal Issue: 6; Other Information: DOI: 10.1103/PhysRevD.78.063510; (c) 2008 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; 99 GENERAL AND MISCELLANEOUS//MATHEMATICS, COMPUTING, AND INFORMATION SCIENCE; ANISOTROPY; APPROXIMATIONS; COSMIC DUST; COSMOLOGICAL CONSTANT; DISTANCE; DISTURBANCES; EINSTEIN FIELD EQUATIONS; GEODESICS; HOT SPOTS; MAXIMUM PERMISSIBLE CONCENTRATION; NONLINEAR PROBLEMS; NUMERICAL SOLUTION; PERTURBATION THEORY; PHOTONS; RED SHIFT; RELICT RADIATION; SIMULATION; SPACETIME; SPHERICAL CONFIGURATION; UNIVERSE
Citation Formats
Sakai, Nobuyuki, Inoue, Kaiki Taro, and Department of Science and Engineering, Kinki University, HigashiOsaka 5778502. Cosmic microwave background anisotropy from nonlinear structures in accelerating universes. United States: N. p., 2008.
Web. doi:10.1103/PHYSREVD.78.063510.
Sakai, Nobuyuki, Inoue, Kaiki Taro, & Department of Science and Engineering, Kinki University, HigashiOsaka 5778502. Cosmic microwave background anisotropy from nonlinear structures in accelerating universes. United States. doi:10.1103/PHYSREVD.78.063510.
Sakai, Nobuyuki, Inoue, Kaiki Taro, and Department of Science and Engineering, Kinki University, HigashiOsaka 5778502. Mon .
"Cosmic microwave background anisotropy from nonlinear structures in accelerating universes". United States.
doi:10.1103/PHYSREVD.78.063510.
@article{osti_21250818,
title = {Cosmic microwave background anisotropy from nonlinear structures in accelerating universes},
author = {Sakai, Nobuyuki and Inoue, Kaiki Taro and Department of Science and Engineering, Kinki University, HigashiOsaka 5778502},
abstractNote = {We study the cosmic microwave background (CMB) anisotropy due to spherically symmetric nonlinear structures in flat universes with dust and a cosmological constant. By modeling a timeevolving spherical compensated void/lump by LemaitreTolmanBondi spacetimes, we numerically solve the null geodesic equations with the Einstein equations. We find that a nonlinear void redshifts the CMB photons that pass through it regardless of the distance to it. In contrast, a nonlinear lump blueshifts (or redshifts) the CMB photons if it is located near (or sufficiently far from) us. The present analysis comprehensively covers previous works based on a thinshell approximation and a linear/secondorder perturbation method and the effects of shell thickness and full nonlinearity. Our results indicate that, if quasilinear and large (> or approx.100 Mpc) voids/lumps would exist, they could be observed as cold or hot spots with temperature variance > or approx. 10{sup 5} K in the CMB sky.},
doi = {10.1103/PHYSREVD.78.063510},
journal = {Physical Review. D, Particles Fields},
number = 6,
volume = 78,
place = {United States},
year = {Mon Sep 15 00:00:00 EDT 2008},
month = {Mon Sep 15 00:00:00 EDT 2008}
}

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