MilestoneTheory & algorithmsConfirmed
A theorem limits quantum query advantages at constant depth
Aug 19, 2026
Guy Blanc and colleagues show that quantum algorithms using a constant number of parallel query rounds can be simulated on most inputs with polynomially many classical queries. This concerns black-box query counts, not an efficient classical simulation of every circuit.
Why it matters
The result narrows where large quantum speedups can arise and clarifies why problem structure and computational depth matter.
Guy Blanc · Jordan Docter · Carmen Strassle · Li-Yang Tan · Stanford
Related
Added Oct 28, 2026. Spotted an error? Tell us and we will review it.