Consequences of an extension of General Relativity on gravitational waves

Abstract

In the beginning, I show that the addition of compact extra dimensions to General Relativity implies the existence of a new polarization of massless gravitational waves and new massive gravitational waves. Then I show that the massive waves create echoes but these echoes can't be observed by current interferometers. Eventually, I explain how the new polarization could be detected and why it is interesting to search for new polarizations.