In November 2015, we will celebrate the centenary of Einstein’s general theory of relativity. The theory, which explains gravity in terms of a curved space-time, has been tested in a number of ways. It has passed all challenges with flying colours. All apart from one. Einstein’s theory predicts the existence of gravitational waves, tiny wobbles of space and time that move at the speed of light. These waves should be created whenever massive objects accelerate; in binary systems, when stars explode and even following the Big Bang at the beginning of the Universe.
In principle, they would allow us to explore the dark side of the universe (especially black holes), but in practice… we just haven’t been able to catch them. In this talk I will explain why gravitational-wave “astronomy” is such an exciting prospect, why the waves are so elusive and why there is every reason to believe that there will be success in the next few years.