# 15th-DEX Workshop - Testing Gravity with Strong Lensing

Slides are here

### Abstract

With the advent of LSST and Euclid, hundreds of new supernovae Type Ia are expected to be observed. Thus the prospects for discovering a sufficient number of gravitational lensed supernovae Type Ia (glSNe Ia) to perform meaningful cosmological tests in the near future are good. In this work I am investigating lensing observables and the intrinsic properties of galaxies acting as strong lenses for glSNe Ia to distinguish between GR and $$f(R)$$ cosmologies. The latter belongs to the family of scalar-tensor gravity theories that do not modify the lensing potential, well however the gravitational potential. Therefore if one would interpret observations of glSNe Ia assuming GR, then one would infer dynamical masses, $$M_{dyn}$$, which are different from those estimated using lensing. A mismatch in the estimates of the lensing and dynamical masses would therefore be a smoking-gun for modified gravity, which strongly motivates research on these types of observational signatures.