Pre-registration: a calibrated test of the independence premise of fault tolerance on public QEC syndrome data (premise meter, frozen protocol)

What this registers The analysis protocol of the premise meter. It tests whether public quantum-error-correction syndrome data agree with an independent-noise "twin" fitted to the same data. It also measures how far each dataset can certify the local-stochastic premise of the threshold theorem. Every analysis choice is fixed in frozen_protocol.json: • configuration eligibility, and the pre-registered subset in g0_selection.json; • the interleaved fit/test split; • the window families; • twin construction: candidate mechanisms from each circuit, an exact parity-moment fit, and a signed quasi-probability simulation with local weights; • the G0 gate decision rule; • the burst classifiers B1 and B2 with their validation targets; • the excess-tail-ratio interval and the certification-horizon conditions; • the model-free certificate's window rule. qpremise_code_at_freeze_79dbf14.zip holds the analysis code at the freeze. The protocol's code_sha256 can be recomputed from it: the SHA-256 over every qpremise/**/*.py file in path order, each file's relative path followed by its bytes with LF line endings. Hypotheses analysed after this registration (on test halves only) H1. After removing windows flagged by the frozen burst classifier, the excess tail ratio R(k) = P_obs(K ≥ k) / P_twin(K ≥ k) has an upper 95% confidence bound ≤ 3 for all k ≤ k_cert. Failure: a lower bound > 3 that replicates on the held-out half. H2. Including burst windows, R(k) > 10 for k ≥ k_b in at least one dataset, and a burst-mixture model fitted to the flagged windows predicts the published repetition-code error floor within a factor of 10. H3. The empirical horizon (power ≥ 0.8 at α = 0.05 against a factor-5 excess) agrees with the exact binomial computation within ±1. At least one dataset certifies k ≥ 10 in whole-patch windows. These are evaluated only on (dataset, window family) pairs that pass the G0 gate under both the stationary (N1) and drift-aware (N5) twins. The model-free certificate (T3) does not depend on the twin. Its threshold ε* is fixed before any certificate is computed. Timing and what had been seen Frozen 2026-10-01 17:31 IST (git commit 79dbf14). Before the freeze, only fit halves had been analysed. The G0 gate (bulk of the window-count distributions only; decision rule frozen) began on the test halves minutes after the freeze. When this record was created, no tail statistic (R(k), H1–H3, burst rates, certificates) had been computed from the test halves, and their tail bins had not been examined. The planned cloud-hardware contrast experiment (H4, H5) is not part of this registration and will be registered separately before any hardware run. Full details are in PREREGISTRATION.md. Protocol SHA-256: 5f7458cfdbe0e203fd9e2bf5d579703509c8374bae53096c37f8f1530540707a