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arXiv · 0807.3872

A comparison of approximate gravitational lens equations and a proposal for an improved new one

V. Bozza
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Abstract

Keeping the exact general relativistic treatment of light bending as a reference, we compare the accuracy of commonly used approximate lens equations. We conclude that the best approximate lens equation is the Ohanian lens equation, for which we present a new expression in terms of distances between observer, lens and source planes. We also examine a realistic gravitational lensing case, showing that the precision of the Ohanian lens equation might be required for a reliable treatment of gravitational lensing and a correct extraction of the full information about gravitational physics.

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V. Bozza. 2008-10-28. A comparison of approximate gravitational lens equations and a proposal for an improved new one. https://doi.org/10.1103/physrevd.78.103005

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