AM = coAM
Statement
Migrated verbatim from co-arthur-merlin § Co-Arthur-Merlin:
The complement class of AM: a problem is in coAM if its complement is in AM. Equivalently, coAM is the class of problems for which a “no” answer has an Arthur-Merlin protocol — Arthur sends a random challenge, Merlin responds, and Arthur can verify “no” answers with high probability.
Notes
source: folklore: the claim carried no citation on the page it was
migrated from, and none was invented.
class: unstated: no citing page says which notion of reduction is meant.
Recording a class the wiki does not state would add a claim.
class: free because a containment between complexity classes is proved
by any argument at all; the reduction-class axis does not discriminate
here, and unstated would wrongly suggest the information is missing.
Recorded during migration and not fixed — these are claims about the source text, not changes to it:
- Definitional (complementation), not a theorem; the migration probably wants a distinct ‘complement-of’ edge type.