THEORY OF NOTHINGNESS: 'UN-SET' THEORY

We construct a Lorentz-invariant effective field theory in which the quantum vacuum is governed by a scalar field N(x) whose ground-state expectation value is non-zero. The framework (i) resolves the cosmological-constant hierarchy without fine-tuning, (ii) predicts a mild red-shift dependence w(z)=-1+β dN/dz distinguishable from ΛCDM, and (iii) imprints a sign-reversing gradient correction on the Casimir force. Using 2018 Planck + DESI DR2 BAO + Pantheon+ SNe we forecast Δχ²≈-4.6 (≈2σ preference). A tabletop differential-Casimir experiment is proposed that can falsify the model at the 10⁻¹² level.