Quantum simulation algorithms for quantum chromodynamics

Quantum Chromodynamics (QCD) is the theory of strong force and it lies at the heart of our understanding of the plethora of experimental observations, as well as predictions for new particle discoveries in collider experiments like LHC at CERN. One of the major outstanding problems that stand in the way of the successful application of the QCD to real-world systems is its inherent computational complexity. Many important problems resist repeated efforts to find efficient classical algorithms to gain insight into the behaviour of basic building blocks of matter.

This naturally leads us to consider other promising computational paradigms that have a potential to overcome the above obstacles such as quantum computing. The emergence of quantum computing was marked by Feynman's insight in 1982 that simulating the evolution of general many-body quantum systems on a classical computer requires exponential resources. This is due to the exponential scaling of the dimension of the underlying Hilbert space with the system size. In contrast, as Feynman observed, the evolution of the quantum system itself requires only polynomial overhead. Since then, there has been steady theoretical progress on manipulation of quantum information and this has stimulated the development of new information processing protocols which rely essentially on the quantum nature of the physical systems and provide applications for scalable quantum computers. Currently, there is a major theoretical and experimental effort towards actually building small to medium-sized quantum computers. This, together with tangible experimental advances opens up avenues not only for novel algorithmic advances but also for bespoke applications of quantum theory to a range of problems that were previously inaccessible.

We aim to exploit recent advances in quantum computing and simulation of physical systems to solve problems in QCD that were previously intractable by traditional classical methods. This will allow us to delve deeper into particle interaction and inspire new efficient quantum methods for simulating fundamental forces of nature.