Research — Quantum computing and sign problems
Summary: A long-standing challenge for lattice field theory is the breakdown of standard importance sampling algorithms when negative or complex numbers appear where these algorithms expect probabilities between 0% and 100%. Such "sign problems" can arise for systems (such as neutron stars) with many more particles than anti-particles, or when considering out-of-equilibrium dynamics. Building on earlier explorations of novel algorithmic approaches designed to reduce the severity of sign problems, I am now applying quantum computing to avoid sign problems entirely. This involves reformulating simple systems in terms of entangled qubits and designing algorithms to simulate them using existing and near-future quantum devices.
Image: This visualization of a qubit illustrates how it allows for complex superpositions of the two states 0 and 1. The resulting interference and quantum entanglement between multiple qubits lies at the heart of quantum computing and its promise to go beyond the capabilities of existing computers.
Related publications: arXiv:2301.02230, arXiv:2112.07651, arXiv:1712.07585
A longer discussion of this project will soon be completed.
Last modified 26 January 2023