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arXiv · 0807.5123

The role of Lambda in the cosmological lens equation

M. Sereno
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Abstract

The cosmological constant Lambda affects cosmological gravitational lensing. Effects due to Lambda can be studied in the framework of the Schwarzschild-de Sitter spacetime. Two novel contributions, which can not be accounted for by a proper use of angular diameter distances, are derived. First, a term 2m b Lambda/3 has to be added to the bending angle, where "m" is the lens mass and "b" the impact parameter. Second, Lambda brings about a difference in the redshifts of multiple images. Both effects are quite small for real astrophysical systems (contribution to the bending < 0.1 microarcsec and difference in redshift < 10^{-7}).

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M. Sereno. 2008-10-30. The role of Lambda in the cosmological lens equation. https://doi.org/10.1103/physrevlett.102.021301

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