Physics Cafe @ St Mary's: 'Testing gravity in the solar system' Einstein’s General Theory of Relativity (GR) represents one of the key milestones in 20th-century science, matching observations on a wide range of scales with ever increasing accuracy. In the last thirty years, interest has been centred around the mysterious nature of "Dark Matter" and "Dark Energy"; the 2011 Nobel Prize for Physics was awarded for observations that seem to strengthen the case for these, but what exactly do we know? Whilst these ideas appear to work in harmony with GR to explain current observations, our poor understanding of them directly has led some to suggest alternative models may need to be developed – but could we distinguish between any of them? How do we actually test theories of gravity? In this talk, Dr Ali Mozaffari will outline the idea of modifying gravity instead and suggest potential ways to test it, within the next few years. Booking for this event has now closed.