Unary Field Theory: The 70-Day Resonance of the Earth's φ-Shroud

The Unary Field Theory (UFT) predicts that the Earth is enveloped by a "φ-shroud"—a local overdensity of the ultralight scalar dark matter field φ (m_φ = 1. 1 × 10⁻²² eV) gravitationally bound to the Earth, with coherence length ξ_φ ∼ 845 km. The φ-shroud possesses a quantum-pressure restoring frequency ωQP = m_φc²/ħ ≈ 1. 72 × 10⁻⁷ Hz, corresponding to a resonance period TQP ∼ 70 days. The lunar tidal forcing (ωₜide ≈ 2. 68 × 10⁻⁶ Hz, ratio ωₜide/ωQP ∼ 15. 6) places the shroud in the stiff regime for daily tides, but the frequency-dependent Love number k₂⁽φ⁾ (ω) ∝ 1/ (ωQP² − ω²) predicts a resonant enhancement of the solid-Earth tide near 70 days, modulated by lunar nodal (18. 61 yr) and perigee (8. 85 yr) precession sidebands. The predicted fractional Love-number drift is Δk₂/k₂ ∼ 10⁻⁵–10⁻⁴ in the 50–100 day band, detectable via cross-spectrum analysis of 20+ years of Global Geodynamics Project (GGP) superconducting gravimeter data, complemented by GNSS displacements and SLR/LLR J₂ periodicity. This is UFT Prediction Paper XI; the unified framework is in the main paper: Zou (2026), doi: 10. 5281/zenodo. 21186809.