A new lineofsight approach to the nonlinear Cosmic Microwave Background
Abstract
We develop the transport operator formalism, a new lineofsight integration framework to calculate the anisotropies of the Cosmic Microwave Background (CMB) at the linear and nonlinear level. This formalism utilises a transformation operator that removes all inhomogeneous propagation effects acting on the photon distribution function, thus achieving a split between perturbative collisional effects at recombination and nonperturbative lineofsight effects at later times. The former can be computed in the framework of standard cosmological perturbation theory with a secondorder Boltzmann code such as SONG, while the latter can be treated within a separate perturbative scheme allowing the use of nonlinear Newtonian potentials. We thus provide a consistent framework to compute all physical effects contained in the Boltzmann equation and to combine the standard remapping approach with Boltzmann codes at any order in perturbation theory, without assuming that all sources are localised at recombination.
 Authors:
 Institute of Cosmology and Gravitation, University of Portsmouth, Dennis Sciama Building, Burnaby Road, Portsmouth, PO1 3FX United Kingdom (United Kingdom)
 Department of Physics and Astronomy, University of Sussex, Pevensey II Building, Brighton, BN1 9QH United Kingdom (United Kingdom)
 Publication Date:
 OSTI Identifier:
 22525875
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2015; Journal Issue: 04; Other Information: Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ANISOTROPY; BOLTZMANN EQUATION; COSMOLOGY; DISTRIBUTION FUNCTIONS; NONLINEAR PROBLEMS; PERTURBATION THEORY; PHOTONS; POTENTIALS; QUANTUM OPERATORS; RECOMBINATION; RELICT RADIATION; S CODES
Citation Formats
Fidler, Christian, Koyama, Kazuya, and Pettinari, Guido W., Email: christian.fidler@port.ac.uk, Email: kazuya.koyama@port.ac.uk, Email: guido.pettinari@gmail.com. A new lineofsight approach to the nonlinear Cosmic Microwave Background. United States: N. p., 2015.
Web. doi:10.1088/14757516/2015/04/037.
Fidler, Christian, Koyama, Kazuya, & Pettinari, Guido W., Email: christian.fidler@port.ac.uk, Email: kazuya.koyama@port.ac.uk, Email: guido.pettinari@gmail.com. A new lineofsight approach to the nonlinear Cosmic Microwave Background. United States. doi:10.1088/14757516/2015/04/037.
Fidler, Christian, Koyama, Kazuya, and Pettinari, Guido W., Email: christian.fidler@port.ac.uk, Email: kazuya.koyama@port.ac.uk, Email: guido.pettinari@gmail.com. 2015.
"A new lineofsight approach to the nonlinear Cosmic Microwave Background". United States.
doi:10.1088/14757516/2015/04/037.
@article{osti_22525875,
title = {A new lineofsight approach to the nonlinear Cosmic Microwave Background},
author = {Fidler, Christian and Koyama, Kazuya and Pettinari, Guido W., Email: christian.fidler@port.ac.uk, Email: kazuya.koyama@port.ac.uk, Email: guido.pettinari@gmail.com},
abstractNote = {We develop the transport operator formalism, a new lineofsight integration framework to calculate the anisotropies of the Cosmic Microwave Background (CMB) at the linear and nonlinear level. This formalism utilises a transformation operator that removes all inhomogeneous propagation effects acting on the photon distribution function, thus achieving a split between perturbative collisional effects at recombination and nonperturbative lineofsight effects at later times. The former can be computed in the framework of standard cosmological perturbation theory with a secondorder Boltzmann code such as SONG, while the latter can be treated within a separate perturbative scheme allowing the use of nonlinear Newtonian potentials. We thus provide a consistent framework to compute all physical effects contained in the Boltzmann equation and to combine the standard remapping approach with Boltzmann codes at any order in perturbation theory, without assuming that all sources are localised at recombination.},
doi = {10.1088/14757516/2015/04/037},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 04,
volume = 2015,
place = {United States},
year = 2015,
month = 4
}

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