Over the years String Theory (ST) has emerged as a compelling candidate for a unified quantum theory of all fundamental interactions including gravity. Indeed, ST provides a natural setup to investigate deep problems both in elementary particle physics and in cosmology, and also to quantitatively address many subtle issues of quantum gravity. ST has also provided many successful ideas and tools to study Conformal Field Theories (CFTs), with or without supersymmetry, and more generally to study Quantum Field Theories (QFTs), not only in their perturbative regime but also at strong coupling. This project, called String Theory & Fundamental Interactions, has as its primary challenge and goal to establish a more solid and predictive connection among the various aspects of this broad research area. It will be devoted to explore in particular the following topics:
A. Nonperturbative effects in QFT B. AdS/CFT correspondence and holography C. String phenomenology and string cosmology D. Formal developments in string theory
The important results that have been obtained in the past few years show that even if these topics might look superficially distinct, they are on the contrary highly intertwined with each other. For example, the use of localization techniques developed to study nonperturbative effects in QFT has been beneficial to explore several issues in holography and more generally in the gauge/gravity correspondence. Furthermore, in many interesting phenomenological and cosmological applications of ST, one makes use of sophisticated formal tools and techniques originally developed for other purposes. We believe that enhancing the cross-fertilization among these different sub-fields will lead to further progress. The participants in this project have complementary expertise, cover a wide range of topics in string and quantum field theories and have a good record of collaborations and interactions among them. This project consists of the elaboration of theoretical models within a rapidly evolving context, which requires close contact and frequent interactions among scientists. Thus, to increase collaborations among the participating teams, we plan to organize common activities, for example informal workshops and periodic meetings, and to promote mobility of the participants among the various nodes of the collaboration.