claimroutineinferred_dep

Transducer runs in polynomial time

Transducer runs in time 2O(B)=(n+2)O(1)2^{O(B)}=(n+2)^{O(1)}
running-time part of the fixed-precision theorem
Claim·§12.2 A dyadic approximation at the specified start·inside thmDeterministic logspace approximation of acceptance probability

Statement (paper)

Each digit query is a halting deterministic computation with O(B)O(B) work bits, so on its fixed input it has at most 2O(B)2^{O(B)} complete configurations and hence runs for at most 2O(B)2^{O(B)} steps. Since there are 2O(B)2^{O(B)} environment encodings, O(K+1)O(K+1) binary-search passes, and K+1K+1 digit queries per numerator, the total running time of the transducer is 2O(B)=(n+2)O(1)2^{O(B)}=(n+2)^{O(1)}.

In plain English

The deterministic transducer that outputs the dyadic approximation runs in time 2O(B)2^{O(B)}, which is polynomial in n+2n+2, because each digit query halts within 2O(B)2^{O(B)} steps and only 2O(B)2^{O(B)} queries are made overall.

Why it's here

This is the running-time part of the parent theorem. It counts configurations to bound each digit query by 2O(B)2^{O(B)} steps, then multiplies by the number of environment encodings, binary-search passes and digit queries. With B=O(log⁡(n+2))B=O(\log(n+2)) the product is (n+2)O(1)(n+2)^{O(1)}, complementing the logarithmic space accounting of the previous claim.
Classified routine:
Standard configuration-counting argument: a halting deterministic machine using O(log n) space runs in polynomial time (it cannot repeat a configuration). Here it is combined with a direct multiplication of the numbers of environment encodings, binary-search passes and digit queries.

Uses

Used by

Nothing in the paper

Sources

PaperOpen
Section
§12.2 A dyadic approximation at the specified start
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sections/conclusion.tex:264
Leannot aligned

Phase 2 aligns this node to a Lean declaration.

Friction

  • info
    inferred_dep
    outline: "Polynomial time by configuration counting" rests on claim-thm-fixed-precision-6