More than a billion years ago, two black holes in a distant galaxy locked into a spiral, falling inexorably toward each other, and collided. "All that energy was pumped into the fabric of time and space itself," says theoretical physicist Allan Adams, "making the universe explode in roiling waves of gravity." About 25 years ago, a group of scientists built a giant laser detector called LIGO to search for these kinds of waves, which had been predicted but never observed. In this mind-bending talk, Adams breaks down what happened when, in September 2015, LIGO detected an unthinkably small anomaly, leading to one of the most exciting discoveries in the history of physics.
Allan Adams is a theoretical physicist working at the intersection of fluid dynamics, quantum field theory and string theory.
Allan Adams is a theoretical physicist working at the intersection of fluid dynamics, quantum field theory and string theory. His research in theoretical physics focuses on string theory both as a model of quantum gravity and as a strong-coupling description of non-gravitational systems.
Like water, string theory enjoys many distinct phases in which the low-energy phenomena take qualitatively different forms. In its most familiar phases, string theory reduces to a perturbative theory of quantum gravity. These phases are useful for studying, for example, the resolution of singularities in classical gravity, or the set of possibilities for the geometry and fields of spacetime. Along these lines, Adams is particularly interested in microscopic quantization of flux vacua, and in the search for constraints on low-energy physics derived from consistency of the stringy UV completion.
In other phases, when the gravitational interactions become strong and a smooth spacetime geometry ceases to be a good approximation, a more convenient description of string theory may be given in terms of a weakly-coupled non-gravitational quantum field theory. Remarkably, these two descriptionswith and without gravityappear to be completely equivalent, with one remaining weakly-coupled when its dual is strongly interacting. This equivalence, known as gauge-gravity duality, allows us to study strongly-coupled string and quantum field theories by studying perturbative features of their weakly-coupled duals. Gauge-gravity duals have already led to interesting predictions for the quark-gluon plasma studied at RHIC. A major focus of Adams's present research is to use such dualities to find weakly-coupled descriptions of strongly-interacting condensed matter systems which can be realized in the lab.