¹ Università degli Studi "Federico II", Napoli. Dipartimento
di Scienze Fisiche
² Osservatorio Astronomico di Capodimonte

Abstract

The
lens equation is derived in the framework of metric tensor
theories of gravity. The effects of the gravitomagnetic
field and of post-post-Newtonian corrections are evaluated
for relevant astrophysical systems. Two main applications
of the lens equation to cosmology are also discussed. The
luminosity distance-redshift relation is corrected for the
effect of gravitational lensing; observations of type Ia
supernovae are considered. Then, depletion curves and giant
luminous arcs in clusters of galaxies are explored as tools
to characterize the dark energy content of the universe.