Convergence of the 10⁷ GeV Cutoff: From Higgs Decay Width to the Generalized Uncertainty Principle

Determining a fundamental spacetime cutoff generally relies on extrapolative assumptions from the Planck scale or Grand Unified Theories (GUT). In this brief report, we present a phenomenological approach to identifying this cutoff. From the decay width of the Higgs boson (Γ_H ≈ 4.1 MeV), we derive an energy cutoff scale at Λ_SVL ≈ 1.2 × 10⁷ GeV. Notably, this single value concurrently yields consistent results across three independent domains: (1) estimating the lightest neutrino mass at 10⁻⁵ eV, (2) establishing a finite maximum energy density limit for the early universe, and (3) defining a minimum length a₀ ≈ 10⁻²³ m, consistent with the Generalized Uncertainty Principle (GUP).