Phys.org October 5, 2020
An international team of researchers (USA – Los Alamos National Laboratory, industry, UK) has developed a hybrid quantum-classical algorithm, called variational fast forwarding (VFF) which is a hybrid combining aspects of classical and quantum computing. Although well-established theorems exclude the potential of general fast forwarding with absolute fidelity for arbitrary quantum simulations, the researchers get around the problem by tolerating small calculation errors for intermediate times to provide useful, if slightly imperfect, predictions. The errors that build up as simulation times increase limits potential calculations. Still, the algorithm allows simulations far beyond the time scales that quantum computers can achieve without the VFF algorithm. The research group confirmed their approach by implementing a VFF algorithm on a two qubit computer to fast forward the calculations that would be performed in a one qubit quantum simulation.
In future work, the Los Alamos researchers plan to explore the limits of the VFF algorithm by increasing the number of qubits they fast forward and checking the extent to which they can fast forward systems…read more. Open Access TECHNICAL ARTICLE
Comparing different quantum simulation strategies. Credit: npj Quantum Information volume 6, Article number: 82 (2020)