String theory, quantum field theory and gauge/gravity duality

• Antragsteller: Dr. Tristan McLoughlin
• Fachliche Zuordnung: Kern- und Elementarteilchenphysik, Quantenmechanik, Relativitätstheorie, Felder
• Förderung: Förderung von 2010 bis 2013
• Projektkennung: Deutsche Forschungsgemeinschaft (DFG) - Projektnummer 170113223

Much of the structure of the world around us and its interactions – the rigidity of the chair beneath us, the light we see or indeed why the stars give off that very light – is currently understood in the terms of quantum theories of gauge fields. As these theories have been highly tested by experiment we have a great deal of confidence that they are correct, at least in their regimes of applicability. However the theoretical tools we have to analyse them, particularly when the interactions are strong, are limited and profound open questions remain. One very novel approach to these problems, which is at the heart of my research, is the remarkable duality between certain quantum theories of gravity and gauge theories. The most studied example has, on the one side, strings moving in the curved space-time AdS5×S5 and is conjectured to be dual to four dimensional N = 4 super-Yang-Mills. This theory though not the same as the gauge theory that describes the strong force shares many of its features. These two theories are dual in that every measurable object in one theory has an alternative, but equivalent, description in the other theory, although the relationship between these can be extremely non-obvious. Most excitingly the duality relates the weakly interacting regime of one theory to the strongly coupled regime of the dual theory. While this makes proving the duality rather difficult, it means that we can understand strongly interacting gauge theories by considering weakly interacting string theories and just as interesting, it implies we can describe theories of quantum gravity by gauge theories. It is the aim of this project to study this duality and make use of the insights gleaned to better understand the physics of both gauge theories and quantum gravity. More specifically, one recent discovery is that examples of this duality seem to be integrable, that is to say they possess an infinite number of conserved quantities, which makes calculational problems much more tractable and may make it possible to actually prove the duality in certain limits. In the proposed project the origin and structure of this integrability is to be considered with an eye to developing tools to calculate interesting observables at all values of the coupling. Furthermore, the methods and results will be generalized towards other, more phenomenologically relevant, theories.

• DFG-Verfahren: Sachbeihilfen