Weak gravitational lensing in spheroidal voids

EZEQUIEL BOERO; OSVALDO M. MORESCHI

Córdoba

Congreso; CosmoSur III; 2015

FaMAF - OAC

We have extended the previous work on gravitational lensing on flatspacetime by O.M. and E.G. [GM11] to cosmological backgrounds; which requires,slight modifications in the discussion previously published.Our expressions include the contributions from spacelike components of theenergy-momentum tensor, that have been systematically neglected in the literature.When applied to the case of thin lens, our equations show that other authors haveneglected a redshift factor in the optical scalars, since they just normally take theequations on a flat background and interchange the role of the interveningdistances by angular diameter distances.Our discussion allows to consider the whole Robertson-Walker spacetime as anadditional gravitational lens which produce convergence but not shear.