A model-independent characterisation of strong gravitational lensing by observables

Understand

When light from a distant source object, like a galaxy or a supernova, travels towards us, it is deflected by massive objects that lie on its path.

• When the mass density of the deflecting object exceeds a certain threshold, multiple, highly distorted images of the source are observed.
• This strong gravitational lensing effect has so far been treated as a model-fitting problem.
• Using the observed multiple images as constraints yields a self-consistent model of the deflecting mass density and the source object.