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.
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- 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.
Unitary normal form for finite bit-query algorithms without extra queries
Statement
For any finite-input standard XOR bit-query algorithm in the ordinary oracle-only model, using at most T queries on every branch, there is an algorithm with the same output probabilities whose evolution consists of an input-independent initial state, input-independent unitaries between exactly T unconditional calls to O_x, and a final measurement. It uses no controlled access to O_x and no more than T oracle calls.
Facts & Assumptions
Given: A finite standard bit-query algorithm in the ordinary oracle-only model, with worst-branch query count at most T.
Quantum query algorithm: in the ordinary oracle-only model, the zero-initialized root and every preparation/nonoracle operation are input-independent, and a T-query algorithm has at most T designated oracle calls on each branch; preparation and other operations retain their separate charges.
Finite instruments can be coherently deferred: finite instruments have coherent unitary dilations with retained outcome records, preserving their branch maps even on entangled data. Newly used dilation and block operations must be accounted for in the chosen model; this denotational theorem asserts no cost bound.
Standard bit-flip query convention: O_x|i,b,w⟩=|i,b⊕x_i,w⟩ and O_x^2=I.
Finite registers and their ordered computational bases: each finite register has an ordered computational basis, and tensor factors may be enlarged by finite work registers.
The computational basis is orthonormal: distinct computational-basis labels are orthogonal.
Proof
The root state and all nonoracle instruments are input-independent by [F1]. Apply [F2] to those instruments only, retaining their observed outcomes and hidden dilation registers. Each dilation and each block control of a known nonoracle operation is then an input-independent unitary on finitely enlarged registers, allowed as a nonoracle operation in this query model; their gate and preparation costs are separate from oracle count. Retaining the orthogonal histories [F5] and using [F2] with the remaining registers as reference preserves the original branch output law. No oracle operation is dilated or replaced by an assumed controlled oracle.
Synchronize the finite execution tree by query number: before slot q, run each retained history's nonoracle segment until its qth query or termination, keeping terminated histories unchanged. These finite controlled segments are input-independent unitaries by step 1.1. At the slot, an active history presents its address and response to the query wires. On an inactive history, controlled swaps instead present a scratch address i_0 chosen as the first computational-basis label (the empty word for a zero-qubit address register) and a scratch target |+⟩=(|0⟩+|1⟩)/√2, preserving the algorithm registers. This address exists because the address register has positive dimension by [F4]. Apply one unconditional O_x and undo the routing swaps. Since X^{x_i}|+⟩=|+⟩ for every i, this acts identically on inactive histories and as the prescribed query on active ones, including their coherent superpositions.
Use slots q=1,…,T, then execute the final nonoracle segments and read the retained output records. Each slot contains exactly one unconditional oracle call by step 2.1, and step 1.1 adds none, so the total is exactly T, including zero when T=0. Histories with fewer queries are padded by inactive slots. Induction over the slots preserves each branch map and hence the final output law. All remaining operations and the initial state are input-independent; no controlled access to an unknown O_x or gate-efficiency bound is assumed.
Depends on
Used by
Dependency tree · two levels
38 results within two dependency steps of this one, each drawn at its shortest distance from it. An arrow runs from a result to what uses it, so the chart reads left to right and ends at this result, which carries a heavier outline. Every node is a link to that result. Click elsewhere on the chart to enlarge it.
Sources
- Andrew M. Childs, Lecture Notes on Quantum Algorithms (17 April 2025) (standard reference, not scraped)
- Ronald de Wolf, Quantum Computing: Lecture Notes, arXiv:1907.09415v6 (standard reference, not scraped)