proof
P14 Bundle factorization
Lean spine source
formal/Bundles.leanFrom the machine-checked spine in formal/ (Mathlib + spine imports). Not self-contained for Lean 4 Web — use the repo or a local lake build.
theorem P14_factorization_implies_equivalent_errors
{f : Error → Action} {c : Error → Bundle}
(h : FactorsThrough f c)
{e₁ e₂ : Error}
(heq : c e₁ = c e₂) :
f e₁ = f e₂ := by
obtain ⟨d, hd⟩ := h
rw [hd]
simp [Function.comp, heq]
/-- A toy sample predicate: there are enough observations for a `K`-dimensional
LHV readout. This deliberately abstracts away constants and horizons. -/