# Research Area D: Theoretical Concepts and Mathematical Foundations

### Research Programme

The experimental research programme of PRSIMA is supported by a strong programme in theoretical physics. Focus areas include effective field theories, lattice gauge theory, perturbative methods, quantum gravity, and topics of string theory and mathematical physics.

We apply effective field theories (EFTs) to a variety of different problems, including flavour physics, collider physics, physics beyond the Standard Model, and low-energy processes. Improving the accuracy of EFT calculations is one of our major aims. Further focus areas of our research are calculating scattering amplitudes beyond the leading order, improving these calculations with all-order resummations of large logarithms, and combining these results with parton-shower programmes.

The lattice QCD group performs simulations on high-performance supercomputers and continues to work on the acceleration of simulation algorithms. Constructing a consistent field theory of fixed-point quantum gravity, as an alternative to string theory, is another focus area. Aspects of string phenomenology, such as string-inspired models of extra dimensions and SUSY extensions of the Standard Model, as well as the moduli spaces resulting from compactification, are also to be explored. Finally, we investigate several topics at the intersection of physics and mathematics are being investigated, including the deep connections between scattering amplitudes, loop integrals, number theory, and algebraic geometry.