Quantum theory and General Relativity are the two main pillars of theoretical physics. Together they describe the real world over a large range of scales, however, individually both have their limitations. Quantum theory cannot account for large scale phenomena such as gravity and the cosmological constant. General relativity breaks down at small scales with the prediction of singularities and cannot explain the thermodynamic properties of black holes microscopically.
String theory provides a theoretical framework where both theories are consistently unified. It provides a very deep connection between gauge theory (open strings) and gravity (closed strings), which in turn led to the AdS/CFT correspondence. This is an example of a gauge/gravity duality, in which the dynamical degrees of freedom of a strongly coupled gauge theory rearrange themselves into degrees of freedom of a weakly coupled gravitational theory. It also provides an explicit realisation of the holographic principle which explains the thermodynamic properties of black holes.
Our research focuses on the geometry of supersymmetry and supergravity, the classification of gravitational solutions in various dimensions, black holes and their applications to the AdS/CFT duality, and the development of holography in more general spacetimes.