theorem
proved
phi_ring_certificate
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IndisputableMonolith.Algebra.PhiRing on GitHub at line 471.
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468 5. φ² = φ + 1 (defining relation) ✓
469 6. N(φ) = −1 (φ is a unit) ✓
470 7. Connection to cost algebra: J(φ) computed ✓ -/
471theorem phi_ring_certificate :
472 -- φ satisfies defining equation
473 (PhiInt.phi * PhiInt.phi = PhiInt.phi + PhiInt.one) ∧
474 -- Norm is multiplicative
475 (∀ z w : PhiInt, PhiInt.norm (z * w) = PhiInt.norm z * PhiInt.norm w) ∧
476 -- Conjugation is involution
477 (∀ z : PhiInt, z.conj.conj = z) ∧
478 -- Conjugation preserves multiplication
479 (∀ z w : PhiInt, (z * w).conj = z.conj * w.conj) ∧
480 -- N(1) = 1
481 PhiInt.norm 1 = 1 ∧
482 -- N(φ) = -1
483 PhiInt.norm PhiInt.phi = -1 :=
484 ⟨phiInt_sq, PhiInt.norm_mul, PhiInt.conj_involution,
485 PhiInt.conj_mul, PhiInt.norm_one, PhiInt.norm_phi⟩
486
487end PhiRing
488end Algebra
489end IndisputableMonolith