The class of decision problems for which a "yes" answer can be verified by a public-coin quantum AM protocol, as follows. Arthur generates a uniformly random (classical) string and sends it to Merlin. Merlin responds with a polynomial-size quantum certificate, on which Arthur can perform any BQP operation. The completeness and soundness requirements are the same as for AM.
Defined by Marriott and Watrous [MW05].
Contains QMA and is contained in QIP[2] and BP•PP (and therefore PSPACE).
No class.