Strong lensing with positive cosmological constant

TL;DR

This paper investigates how a positive cosmological constant affects strong gravitational lensing, calculating deflection angles and time delays, and compares these theoretical predictions with observations of a specific quasar lens system.

Contribution

It provides new calculations of lensing effects considering a positive cosmological constant and compares these with real observational data.

Findings

Deflection angles are affected by the cosmological constant.

Time delays in lensing are influenced by the cosmological constant.

Comparison with SDSS J1004+4112 shows consistency with theoretical predictions.

Abstract

Strong lensing by an isolated spherically symmetric mass distribution is considered in presence of a positive cosmological constant. Deflection angles and time delay are computed and compared to the multiple image of the quasar SDSS J1004+4112.