Particles, Fields and Strings at Liverpool

With the discovery of the Higgs boson at the Large Hadron Collider, the Standard Model (SM) of Particle Physics is established at the electroweak scale and successfully describes a plethora of experimental data. Similarly, the Standard Cosmological Model is grounded in observational data. Yet, deep and profound mysteries remain in our understanding of the Universe. The existence of Dark Matter (DM) necessitates new physics Beyond the SM (BSM), and crucial issues concerning dark energy and the unification of gravity with the other forces remain unaddressed. Meanwhile, the mathematical structures that underlie Quantum Field Theory (QFT) are far from fully explored; and there are important open questions about the dynamics of matter within the SM, especially in extreme conditions. With the research proposed in three complementary Science Areas, the Liverpool Consortium bid is addressing these fundamental problems.

`String Phenomenology and Cosmology'

In view of the experimental data, resolution of the many shortcomings of the contemporary paradigms can only be obtained by the consistent fusion of gravity and the gauge interactions. String theory provides the leading mathematical framework to explore the unification of the gauge and gravitational interactions, and string phenomenology is the area of string theory that links string theory and observational data. The research proposed in `String Phenomenology and Cosmology' aims at bridging the gap between theoretical advances at the forefront and observational reality. The proposed research will explore the basic symmetries that underlie string theory, aiming to unravel the cosmological evolution near the quantum gravity scale, as well as extract the predictions of string vacua for contemporary experimental searches, including collider, gravitational wave experiments and quantum sensor searches for ultra-light particles.

`Precision QFT for Particle Physics'

will use their expertise in higher-order perturbative Feynman diagram calculations and precision phenomenology to (i) improve our understanding of QFT by constructing the a-function for scale-invariant quantum gravity, (ii) perform cutting edge 4-loop and 5-loop computations, (iii) match perturbative and lattice renormalisation schemes, (iv) improve the SM predictions for (g-2) and quark flavour physics to unprecedented precision, (v) use effective field theory descriptions to search for BSM physics, and (vi) explore BSM scenarios which address the shortcomings and anomalies of the SM and possibly provide a DM candidate. The proposed research will provide crucial theoretical results and tools for these endeavours. It will contribute to the exploitation and planning of current and future experiments at the energy and precision frontier, including DM searches.

`Lattice Quantum Field Theory'

will continue to exploit state-of-the-art high performance computers to attack questions about strongly-interacting particles, examples being: ever-more precise calculations of the internal structure and decays of bound states of quarks known as hadrons; the properties of the plasma-like medium formed under the extreme temperatures and densities found at the very beginning of the Universe and now recreated in energetic collisions between atomic nuclei at CERN; new theories that explain the Higgs boson as a composite of still-more elementary particles; models incorporating a supersymmetry relating fermions to bosons which inform our understanding of quantum gravity; models in two dimensions underlying the electronic properties of exotic new materials; and the development of new quantum algorithms to tackle hitherto inaccessible questions relating to dense, evolving matter.