Theoretical Physics - From Outer Space to Plasma

A pressing question in our quest to understand the Universe is how to unify quantum mechanics and gravity, the very small and the very large.

In this talk, Dr Elliott Bentine shall discuss how recent experiments have exploited machine-learning techniques, both to optimize the operation of these devices and to interperet the data they produce. Modern table-top experiments can engineer physical systems that are deeply into the quantum mechanical regime. These cutting-edge instruments provide new insights into fundamental physics, and a pathway to future devices that will harness the power of quantum mechanics. They typically require complex operations to prepare and control the quantum state, involving time-dependent sequences of magnetic, electric and laser fields. This presents experimental physicists with an overwhelming number of tunable parameters, which may be subject to uncertainty or fluctuations.

Professor Andre Lukas will discuss how string theorists have started to use methods from data science - particularly machine learning - to analyse the vast landscape of string data.

Professor Ard Louis gives a basic introduction to deep learning for physicists and addresses a few questions such as: Is the hype around deep learning justified, or are we about to hit some fundamental limitations? In less than ten years, machine learning techniques based on deep neural networks have moved from relative obscurity to central stage in the AI industry. Large firms such as Google and Facebook are pouring billions into research and development of these new technologies. The use of deep learning in physics is also growing exponentially. Can physics help us understand why deep learning works so well? And conversely: How can deep learning provide new insight into the world around us?

Ian Shipsey give an update on the department and introduces the next three talk on 'AI in Physics'.

In this talk Subir Sarkar will explain how deflagration supernovae have been used to infer that the Hubble expansion rate is accelerating, and critically assess whether the acceleration is real and due to `dark energy’.

In this talk, Philipp Podsiadlowski will explain how this energy (sometimes) creates a visible fireball, before going on to explain the role of supernovae in the production of the heaviest elements in the periodic table.

In this talk, James Binney will outline the physics that leads to prodigeous release of energy in core-collapse and deflagration supernovae.

To study the Higgs boson at the LHC we also need to understand how highly energetic quarks and gluons interact, among themselves and with the Higgs. These interactions are described by quantum field theory, a beautiful mathematical framework that combines quantum mechanics with Einstein’s theory of special relativity. In recent years, our understanding of quantum field theory has progressed significantly, allowing us to develop a new generation of accurate theoretical predictions for key LHC reactions. In this talk, I will highlight some of the ideas behind this progress, and illustrate how they are being applied to investigate the Higgs sector at the LHC.

We learn about the Higgs Boson and its interactions at the LHC by examining the debris produced by colliding protons head-on at unprecedented high energies. However, we know from our theory of strong interactions - quantum chromodynamics (QCD) - that protons themselves are highly complex bound states of more fundamental 'quarks', held together by the force carriers of QCD, the 'gluons'. The question is then: how do we go from the collision of these complicated protons to a theoretical prediction that we can use to test the properties of the Higgs boson itself? In this talk, I will discuss what we know about the proton, and how we apply this to LHC collisions and our understanding of the Higgs sector.