IP ⊆ SZK

IP is contained in SZK.

Statement

Migrated verbatim from zero-knowledge-proof § Other results:

  • All languages in IP (= PSPACE) have statistical ZK proofs — BGG+90

Notes

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:

  • SUSPECTED MATHEMATICAL ERROR (reported, not fixed): as written this says IP = PSPACE is contained in SZK. But SZK is contained in AM \cap coAM, so SZK = PSPACE would collapse the polynomial hierarchy. The actual BGG+90 result is that every language in IP has a COMPUTATIONAL zero-knowledge proof ASSUMING one-way functions exist (with statistical/perfect ZK obtained only in the multi-prover or argument settings). The bullet drops the OWF hypothesis AND upgrades computational ZK to statistical ZK.
  • Consequently the hypothesis set is also wrong: the real edge is conjunctive {interactive-proof-systems, hash-function(OWF)} computational-zero-knowledge (content/Complexity/computational-zero-knowledge.md exists).
  • This is the single most serious claim-level defect found in this chunk; the page is status: stub and its .fact-check queue entry should be checked.