Finding #20 (Super-Blueprint §3.2). surprise_residual was Euclidean Gram-Schmidt
on flat 32-coefficient vectors — metric-blind (it ignored the (+,+,+,+,-)
signature and the blade grade structure), so "inside the admissible span" was
judged by the wrong geometry.
Operator math (core/physics/surprise.py):
- Exact metric-orthogonal projection: solve the normal equations G c = r
(G_ij = cga_inner(b_i,b_j), r_i = cga_inner(b_i,x)) via lstsq, under cga_inner
(32-vec) / eta (5-vec).
- Fail-closed (typed SurpriseResidualError) on a metric-degenerate span, keyed on
rank(G) < rank(B) — a null direction with no reciprocal (lone n_o). Refines the
literal "rank(G) < k": mere linear dependence among non-null columns is admitted
(lstsq projects onto the span), so a redundant live basis [1, source] and the
non-degenerate pair {n_o, n_inf} are admitted; only a lone n_o is refused. The
disclosure names the Gram null-space direction (not just zero-diagonal columns).
- Reconciled productivity polarity: productive_transfer = low Procrustes AND low
surprise (was `sur_norm >= 0.0`, always true). High surprise routes to discovery
(split follow-up). Corrects the ledger's transfer/discovery conflation.
Adversarial verification (3 independent lenses) found, and this fixes:
- HIGH soundness hole: sur_norm was the reversion pseudo-norm, which VANISHES on
a nonzero metric-null residual (the n_o/n_inf light cone) -> false-zero surprise
-> an out-of-span light-cone probe was wrongly admitted as in-span. Now the
DEFINITE (Euclidean) norm of the residual: the projection stays metric-exact,
the magnitude is 0 iff nothing is unexplained.
- HIGH regression: the analogical-transfer harness called surprise_residual
OUTSIDE its try/except, so a degenerate source crashed the whole run. Now
guarded: records a refused case and continues.
- grade-support `allowed` -> exact-nonzero (removes a spurious-leak edge under
coefficient amplification of sub-tolerance grade dust).
DiscoveryCandidate wiring into the contemplation loop is split to its own
follow-up (a distinct cross-cutting surface). Off-serving (nothing in
serving/runtime imports core.physics.*). Tests: 15 behavioral tests
(metric-vs-Euclidean divergence, null-cone regression, null refusal +
combination-degenerate disclosure, 5-vector branch, polarity); 139-test physics
sweep green; ruff clean.