Making waves!

Interviewer: Sam Walter (Interviewer, Ideas Lab)
Guest: Professor Alberto Vecchio
Recorded: 17/03/2014
Broadcast: 17/03/2014

Sam: Welcome to this Ideas Lab Predictor Podflash today with Professor Alberto Vecchio, who’s Professor of Astrophysics at the School of Physics and Astronomy, here at the University of Birmingham. What’s the theory behind gravitational waves?  

Alberto: Gravitational waves are our fundamental prediction of Einstein’s Theory of General Relativity. The theory says that if there are large concentrations of mass, moving at very high speed, then they will produce ripples on the ocean of the space time and these ripples propagate at the speed of light are gravitational waves. 

Sam: So what’s the nature of the work that you’re doing here at the University of Birmingham in gravitational waves?

Alberto: The work we are doing in Birmingham on gravitational waves is on several fronts. Gravitational waves are a fundamental prediction of Einstein’s Theory of General Relativity. There is indirect evidence of their presence through observations of radio pulses whose orbit is shrinking down because the systems are losing energy through gravitation wave emission and one key goal in science right now is to have instruments that allow us to detect directly gravitational radiation and use this as a new tool to study the universe. Therefore we are working on the technology to build this new class of telescopes. These are laser interferometers. We have an active programme in that direction as well as working on aspects that are related to the observations in order to dig out from the data very very weak signals and to study the astro-physics related to that. In fact we think that by using ground based laser interferometers as a new class of telescope, we will be able to observe directly the radiation in gravitational waves emitted for example from black hole binary systems and neutron star binaries. 

Sam: What would the discovery of hard scientific evidence for gravitational waves mean for the future of cosmology and particle physics?

Alberto: The announcement of the results from the Bicep collaboration is the first indication, direct indication, of an inflationary period in the very early universe.  This means that gravitational waves have left a signature in the cosmic macro background maps. It means that we have now a means in order to try to extract information about this period which has eluded direct observations so far. It provides a very challenging area in which we need to bring together new ideas of fundamental physics, particle physics and test them at very high energy at which we haven’t been able to do so far. It therefore also boosts a more vigorous effort in general on gravitational wave searches that are going to be seen as one of the key mechanisms through which we can learn new information about the universe. 

Sam: So where is this area of science going in the next five years?

Alberto: Well, there are a number of experimental efforts that are trying to push the research in new directions in order to broaden the observational windows that we have to study the universe. Also the early universe and also compact astro-physical objects such as black holes. The quest for a direct detection of gravitational waves has been there for a number of years.  We have really many ways in which we could achieve this direct detection and therefore opening a new observational window on the universe. Ground-based laser interferometers on which we work in Birmingham are expected to achieve these direct detections in the next five years or so. This would be a very important step forward for the future for the study of cosmology inflation. Clearly the fact that we have an initial indication of the presence of an inflationary epoch means that the effort in that direction, both experimental and also theoretical, will grow and we may have many more surprises in the future. 

Sam: Professor Albert Vecchio, thank you very much.