I just came across an article about Cornell University professor Eanna Flanagan, whose research involves trying to detect grativational waves. Notes the article:
Now, nearly two decades after leaving Ireland to study for his doctorate under the famous relativist Kip Thorne at the California Institute of Technology, [Flanagan's] work focuses on predicting the size and shape of gravitational waves. These were forecast by Einstein's 1916 Theory of General Relativity but have never been directly detected.
My "watered-down" introduction to general relativity can be accessed here.