Physics Theories Simulation

Quantum field theories, by their nature, are rife with infinities. To connect theoretical predictions from QFT calculations to experimental results, these infinities must be dealt with via a process called regularization and renormalization. The only known generic method for doing so non-perturbatively is by implementing the field theory on a lattice, i.e. by discretizing space-time. An additional benefit of working on a lattice is that it allows one to simulate the theory on a computer, providing first-principle calculations of the properties of strongly coupled theories, including QCD.
This numerical simulation of Euclidean space-time correlation functions currently provides the only ab-initio method for extracting information about low-energy QCD/nuclear physics, with quantifiable errors. Current lattice QCD simulations allow for the measurement of light hadron masses, scattering parameters for certain few-body scattering events and the spectrum of several light hadrons. However, due to the limitations of Monte Carlo importance sampling, there are many questions that cannot be addressed with these tools, including the nature of the QCD phase diagram, particularly for large nuclear density, the real-time behaviour of quarks-gluon plasmas and even the masses of any but the lightest hadrons and nuclei.
The limitations of Monte Carlo also affect our ability to learn about the properties of high-energy QCD, including the structure of parton showers, as seen in LHC collisions. The Lattice Gauge Theory Simulation project will investigate if and how quantum devices and methods, rather than traditional Monte Carlo methods, may allow many of these questions to be explored. Another area taking centre-stage in physics research today is the physics of neutrino oscillation (periodic conversions of one neutrino flavour into another during propagation). The project Quantum Simulation of Collective Neutrino Oscillations will explore some of the least understood aspects of neutrino oscillations, as for example their dynamics in extreme environments such as supernova cores, where neutrino densities are so high that neutrinos influence each other so that the flavour evolution equations become highly non-linear. As this is intrinsically a quantum mechanical process, the goal of this project is to develop methods for simulating collective neutrino oscillations on a quantum computer.