How statement and proof provenance work
The first chip identifies the source of the statement or construction; the second identifies the source of its local proof or verification.
- Literature-sourced: the exact statement appears in a cited source; only wording and notation differ.
- AI-adapted: a semantically identical restatement of literature-sourced material, modulo indexing, notation, and boundary cases adopted by the library.
- AI-generated: a genuinely novel statement formulated by AI, with no source for the claim itself.
These labels describe origin, not correctness: citations and verification chips remain separate evidence.
Polynomial space oracle absorption
Statement
.
Facts & Assumptions
Given: the objects and hypotheses in the statement above.
Fix a total language . An oracle machine writes a query word and receives its membership bit in in one answer step. Query writing counts toward time and the query tape toward space. A polynomial time clock bounds every branch for every oracle. and are deterministic and nondeterministic polynomial-time oracle classes, respectively; the latter equivalently uses a polynomial-length witness and a deterministic polynomial-time -oracle verifier. Use the conventions of the stated convention and the stated convention. For and , replace the deterministic predicate in the stated convention by a predicate; level zero is . Define by deterministic polynomial space under the charged-query convention. For a language class , and . Finally . With a fixed base oracle, a machine may query both and a language ; encode this by the tagged union . (Relativized complexity class).
The class PSPACE is the union of all deterministic polynomial-space classes: The class NPSPACE is the union of all nondeterministic polynomial-space classes: Equivalently, a language lies in PSPACE when there is a deterministic multitape Turing machine deciding using at most space for some constant , and similarly lies in NPSPACE when there is such a nondeterministic decider. The meanings of and are those of the stated convention. (The classes PSPACE and NPSPACE).
TQBF lies in PSPACE, and every language in PSPACE polynomial-time many-one reduces to TQBF. Therefore TQBF is PSPACE-complete. (TQBF is PSPACE-complete).
Proof
For a nondeterministic oracle machine with clock , enumerate all branch-choice strings of the bounded length and replay each branch. Each TQBF query has length at most under the charged-query convention. Decide it by the polynomial-space algorithm supplied by TQBF membership in PSPACE, then reuse that workspace. A branch counter, a machine configuration and the query workspace all have polynomial size; accepting when one replay accepts yields a deterministic polynomial-space decider. Zero-query branches use the same procedure.
For any PSPACE language, its polynomial-time many-one reduction to TQBF computes one polynomial-length query. Accept exactly when the oracle answers YES. This is a deterministic polynomial-time oracle decider on every input, proving the other containment.
Depends on
Used by
Dependency tree · two levels
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