Chapter 3: The Parity Bridge: Weak-Sector Polarity Seeds Life

Among the four primitive holonomy sectors at E₁, only the weak sector admits a nontrivial polarity functional into the split-complex idempotent codomain 2_τ. The Parity Bridge Theorem establishes that weak-sector chirality provides the unique polarity seed that SelfDesc closure amplifies into stable self/non-self distinction, making the weak sector the unique bridge from E₁ to E₂.