Particle Theory at the Higgs Centre

There are two types of fundamental forces in Nature: those responsible for particle interactions at subatomic scales and those responsible for the large scale structure of the universe. The former is described by Quantum Field Theories (QFT) such as the Standard Model(SM). Currently, our understanding of Nature at the most fundamental level is at the crossroads. In 2012, the LHC at CERN collided protons at higher energies than ever before, and observed sufficient collisions to find a significant excess at 125 GeV, consistent with the Higgs boson of the SM. Over the last three years it has become evident that this is indeed a SM Higgs, responsible for generating masses for vector bosons, leptons and quarks. Currently data at even higher energies is being taken at LHC, and it should soon become clearer whether there is more physics at the TeV scale, or whether we need to build machines capable of going to even higher energies. At large scales the European Planck satellite has given the most precise measurements of the cosmic microwave background (CMB) and it is an open question to determine the particle physics model best capable of describing the physics underlying the large scale properties of the Universe. Thus at both small and large scales, this is a transformative time in fundamental physics.

Our programme of research at the Higgs Centre for Theoretical Physics in Edinburgh is designed to be at the forefront of these new discoveries: indeed Peter Higgs himself is Emeritus Professor here. Specifically, we provide theoretical calculations, using pen and paper, and the most powerful supercomputers, of both the huge number of background processes to be seen at LHC due to known physics, and the tiny signals expected in various models of new physics, in order to discriminate between signal and background, and thus maximise the discovery potential of the LHC.

In parallel, we will attempt to understand the more complete picture of all the forces of
Nature that may begin to emerge. The fundamental force responsible for large scale structure is described Einstein's General Theory of Relativity (GR). During the last three decades, string theory has emerged as a conceptually rich theoretical framework reconciling both GR and QFT. The low-energy limit of String Theory is supergravity (SUGRA), a nontrivial extension of GR in which the universe is described by a spacetime with additional geometric data. Members of the group have pioneered approaches to deriving observable cosmological consequences of String Theory, to studying how the geometrical notions on which GR is predicated change at very small ("stringy") distance scales, and the systematic classification of SUGRA backgrounds. The group is also engaged in using these theories to improve calculations in existing field theories.

In summary, our research will impinge on both theoretical and computational aspects relevant to probing the phenomenology of incoming LHC data, and will also encompass a wide range of topics in QFT and gravitational aspects of String Theory, impinging on cosmology, particle physics and on the very nature of String Theory itself.

The Higgs Centre is involved in a wide variety of outreach activities. We have a unique task of developing and supporting public interest in the work of our retired Professor Emeritus Peter Higgs. We receive information almost on a daily basis of press coverage of him or the Higgs boson by media organizations all over the world. We have developed a massive open online course (MOOC) on the discovery of the Higgs Boson, which ran in 2014, 2015, and 2016 fostering this appreciation of cutting edge particle physics in thousands of interested participants in a non-mathematical manner. We have reached over 25,000 participants already.

The range of activities carried out by Higgs Centre staff members includes public talks in Edinburgh, Europe and beyond, film showings within the Higgs Centre, a new workshop series for secondary school teachers, expert interviews in the media (radio and written press) and press releases about our work. We reach non-typical audiences through the Edinburgh Festival Fringe and the Pint of Science Festival. These successful activities will continue alongside plans for increase through greater personal initiative by staff members and cooperation with organizations including the University, Particle Physics 4 Scottish Schools and the Scottish Schools Education Research Centre.

The Centre is also involved in various engagement activities through its affiliation with the Maxwell Institute, whose vision is to maintain a strong connectivity to the world outside theoretical science. To deliver this vision, the Maxwell Institute aims to enhance the breadth of theoretical research addressed at the two universities, to expand its impact on a range of applications to other academic areas, and to increase the reach and impact of our research by promoting collaborations with other academic disciplines, industry and commerce, and the engagement of the public.

Members of the Centre were also involved in the inauguration of the new COST Action QSpace, whose networking activities aim to defragmentise research efforts in theoretical particle physics across Europe and to bridge the gap between theory and experiment in these areas, and also to ensure fair gender representation and foster participation of early stage researchers, in a manner which will impact on science and society at large through the revolutionary understanding of fundamentals of theoretical physics it attains. To this aim, QSpace has set up a Working Group with the specific goal of providing a platform for the joint training of young researchers, and for promoting scientific culture and awareness to school pupils, young women and the general public through various outreach schemes.

We have impacted the high performance computing industry and consequently all of scientific computing in a quite unique way. We have patented novel approaches to supercomputer design with IBM in 2014, following on from our joint project to design the IBM BlueGene/Q system with them. Since that project finished we have worked with Intel to produce high performance computing codes for their processors, and they have invested to create an Intel Parallel Computing Centre in the Higgs Institute for Theoretical Physics.