Nonlinear relativistic corrections to cosmological distances, redshift and gravitational lensing magnification: I. key results

Obinna Umeh*, Chris Clarkson, Roy Maartens

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

62 Downloads (Pure)

Abstract

The next generation of telescopes will usher in an era of precision cosmology, capable of determining the cosmological model to beyond the percent level. For this to be effective, the theoretical model must be understood to at least the same level of precision. A range of subtle relativistic effects remain to be explored theoretically, and offer the potential for probing general relativity in this new regime. We present the distance-redshift relation to second order in cosmological perturbation theory for a general dark energy model. This relation determines the magnification of sources at high precision, as well as redshift space distortions in the mildly non-linear regime. We identify a range of new lensing effects, including: double-integrated and nonlinear-integrated Sachs-Wolfe contributions, transverse Doppler effects, lensing from the induced vector mode and gravitational wave backgrounds, in addition to lensing from the secondorder potential. Modifications to Doppler lensing from redshift space distortions are identified. Finally, we find a new double-coupling between the density fluctuations integrated along the line of sight, and gradients in the density fluctuations coupled to transverse velocities along the line of sight. These can be large and thus offer important new probes of gravitational lensing and general relativity. This paper accompanies paper II (Umeh, Clarkson and Maartens 2014 Class. Quantum Grav. 31 205001), where a comprehensive derivation is given.

Original languageEnglish
Article number202001
Pages (from-to)202001
JournalClassical and Quantum Gravity
Volume31
Issue number20
Early online date1 Oct 2014
DOIs
Publication statusPublished - 1 Oct 2014

Keywords

  • Cosmology
  • Lensing
  • Perturbation theory
  • RCUK
  • STFC
  • ST/H002774/1

Fingerprint

Dive into the research topics of 'Nonlinear relativistic corrections to cosmological distances, redshift and gravitational lensing magnification: I. key results'. Together they form a unique fingerprint.

Cite this