South East Particle Theory Alliance Sussex - Royal Holloway - UCL (SEPTA)

The proposed research joins scientists of the particle theory groups at Sussex, Royal Holloway and University College London in the hunt for new physics under three broad headings:


Collider and Low Energy Phenomenology:
Particle collisions at the energy frontier, presented by the Large Hadron Collider, allow to produce or rule out conjectured new particles thousands of times as heavy as the proton. At intensity frontier, extremely precise measurements of particle interactions allow to probe for even heavier particles in an indirect fashion. Here we explore and combine both directions to unravel the structure of the world at smaller distances than ever, asking questions such as: what makes the known particles so much lighter than the Planck mass of quantum gravity? What is Dark Matter? Is there a unified theory of matter and forces? And how can we best use present and future experiments to shine light on them?

Particle Astrophysics and Cosmology:
One of the most active areas of research in the past decade has been at the interface between particle physics and cosmology. In order to understand the history of the Universe we must understand physical laws in the first moments of the Big Bang, when temperatures and particle energies were huge. Conversely, by detailed observations of the universe today we can trace back the conditions and make deductions about physical laws at high energies. Our research will tackle big questions about the universe: Why is there more matter than antimatter? What is the nature of neutrinos and dark matter? Can we use gravitational waves to look at the first picoseconds of the universe? How can the new quantum technology be used to search for dark matter and other invisible particles? And how can quantum theory and gravity be combined, and can we see their joint effects in the cosmos?

Quantum Field Theory:
The recent discovery that Standard Model-like theories can be fundamental and predictive up to highest energies without being asymptotically free has opened a door into uncharted territory. These novel theories offer alternative ways to UV complete the Standard Model and to address its open challenges from an entirely new angle. Our research will focus on the systematic evaluation of these new types of theories, including the construction of benchmark models beyond the Standard Model. We combine these studies with our continuing quest towards a quantum version of general relativity. Predictions of these scenarios will be contrasted with data from particle colliders and cosmology.