Deviations from Einstein's Gravity at Large and Short Distances

In this talk I will describe some recent results on the sensitivity of resonant mass detectors shaped as a hollow sphere to scalar gravitational radiation. Detection of this type of gravitational radiation will signal deviations from Einstein’s gravity at large distances. I will then discuss a class of experiments aiming at finding deviations from Einstein’s gravity at distances below 1 cm. I will review the main experimental difficulties in performing such experiments and evaluate the effects to be taken in account.