This week, they published details of their experiments using a quantum computer to optimise a portfolio rebalancing strategy. QxBranch’s team, which was acquired by Rigetti in July this year, has been collaborating with CBA for a number of years and had developed a quantum computing simulator for the bank that could run on cloud or on-premises infrastructure.
They implemented and evaluated a portfolio rebalancing use case on an idealized simulator of a gate-model quantum computer. The characteristics of this exemplar application included trading in discrete lots, non-linear trading costs, and the investment constraint. Experimental analysis demonstrated the potential tractability of this application on Noisy Intermediate-Scale Quantum (NISQ) hardware, identifying portfolios within 5% of the optimal adjusted returns and with the optimal risk for a small eight-stock portfolio. (Computerworld)