Spacetime perspective of Schwarzschild lensing

By S. Frittelli, T. Kling, E. Newman. 2000

200 citations recorded by the source corpus.

(November 29, 1999)We propose a definition of an exact lens equation without reference to a background spacetime,and construct the exact lens equation explicitly in the case of Schwarzschild spacetime. For theSchwarzschild case, we give exact expressions for the angular-diameter distance to the sources aswell as for the magnification factor and time of arrival of the images. We compare the exactlens equation with the standard lens equation, derived under the thin-lens-weak-field assumption(where the light rays are geodesics of the background with sharp bending in the lens plane, andthe gravitational field is weak), and verify the fact that the standard weak-field thin-lens equationis inadequate at small impact parameter. We show that the second-order correction to the weak-field thin-lens equation is inaccurate as well. Finally, we compare the exact lens equation with therecently proposed strong-field thin-lens equation, obtained under the assumption of straight pathsbut without the small angle approximation, i.e., with allowed large bending angles. We show thatthe strong-field thin-lens equation is remarkably accurate, even for lightrays that take several turnsaround the lens before reaching the observer.I. INTRODUCTION

Subfields: Astronomy and Astrophysics, Nuclear and High Energy Physics

View Paper: https://www.semanticscholar.org/paper/af63f0141c508a44e2012ccf1df220aea19c92ea

Citations in the corpus

• Gravitational lensing by black holes in the 4D Einstein-Gauss-Bonnet gravity (2020, unknown): “Later on, using a different formulation, an exact lens equation and integral expressions for its solutions were obtained [48].”