Theoretical Studies in Elementary Particle Physics

Neutrino oscillations have provided the first evidence of physics beyond the standard model of particle physics. The work proposed aims to advance the theoretical understanding of neutrino oscillations and their connections to other phenomena, in order to make progress in our understanding of high energy physics and astrophysics. Some of the goals are understanding direct connections between experimental observables and fundamental physics parameters; understanding degeneracies between different standard and potential new physics parameters and how these degeneracies can be lifted by using different types of observables; exploring new types of observables that could be measured with present and proposed detectors in order to increase our physics knowledge and understanding; exploration of new theoretical frameworks and models that can accommodate present observations and can have interesting predictions for future measurements; the development of frameworks and models that can potentially connect neutrinos to other particle physics or astrophysics phenomena.Interactions of fundamental particles and their hidden interrelations are sharply probed by their quantum scattering. Its study can thus lead to a thorough understanding of their properties and to efficient calculational tools. Work is planned to use this approach to understand whether all theories of gravity can be expressed in terms of building blocks describing other interactions; to explore their high-energy properties and construct a framework for exploring the consequences on observables of symmetries that do not act locally or linearly; to understand and exploit the connection between scattering amplitudes and classical physics in gravitational theories. This novel approach will also give a new perspective on certain elusive theories that describe interactions of certain massless particles in string theory. Holography or holographic duality -- the property of certain gravitational theories to be described by non-gravitational ones in one-lower dimension -- have improved our understanding of gravitational and nongravitational theories alike. This framework will be used to explore the connection between properties of space-time and infinite symmetries of the corresponding dual theories. In addition, novel approaches will be used to answering the long-standing question of the classification of certain integrable quantum field theories in two dimensions.