Quantum circuits scale linearly with system size, research confirms

Tobias Hartung of Northeastern University and Karl Jansen of The Cyprus Institute have demonstrated that quantum imaginary time evolution guarantees convergence to the global minimum for specific systems, avoiding a common roadblock known as critical slowing down. Their work establishes that the required computational time for this evolution scales linearly with system size and inverse energy gap, offering a potential solution to the exponential resource scaling that currently limits many quantum algorithms. This research confirms the efficiency of quantum imaginary time evolution when applied to problems including ground state preparation, combinatorial optimisation, and quantum machine learning, particularly for systems with bounded order interactions. The team further shows this evolution can…