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Title: Geodesic curve-of-sight formulae for the cosmic microwave background: a unified treatment of redshift, time delay, and lensing

In this paper, we introduce a new approach to a treatment of the gravitational effects (redshift, time delay and lensing) on the observed cosmic microwave background (CMB) anisotropies based on the Boltzmann equation. From the Liouville's theorem in curved spacetime, the intensity of photons is conserved along a photon geodesic when non-gravitational scatterings are absent. Motivated by this fact, we derive a second-order line-of-sight formula by integrating the Boltzmann equation along a perturbed geodesic (curve) instead of a background geodesic (line). In this approach, the separation of the gravitational and intrinsic effects are manifest. This approach can be considered as a generalization of the remapping approach of CMB lensing, where all the gravitational effects can be treated on the same footing.
Authors:
 [1] ;  [2] ; ;  [3]
  1. APC, (CNRS-Université Paris 7), 10 rue Alice Domon et Léonie Duquet, 75205 Paris (France)
  2. Department of Physics, Tokyo Institute of Technology, Tokyo 152-8551 (Japan)
  3. Yukawa Institute for Theoretical Physics, Kyoto University, Kyoto 606-8502 (Japan)
Publication Date:
OSTI Identifier:
22375805
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2014; Journal Issue: 10; 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; DIAGRAMS; GRAVITATIONAL LENSES; LIOUVILLE THEOREM; PHOTONS; RED SHIFT; RELICT RADIATION; SCATTERING; SPACE-TIME; TIME DELAY