This technical note presents a fit‑free derivation of a minimal ultraviolet (UV) length scale within the BRane Interface Substrate Model (BRISM), achieved entirely without using the gravitational constant G. The only dimensional input is the experimentally measured proton Compton wavelength, and the fine‑structure constant is taken as an external empirical input to avoid any circularity. All remaining elements follow from BRISM’s internal interface geometry, including the fixed structural scale ε = 1/π² and an isotropic three‑dimensional projection factor (1 + ε/√3). No SU(5) exponential correction is applied in this conservative evaluation. Using CODATA 2022 inputs, the resulting UV minimal length evaluates to L = 1.61265×10⁻³⁵ m, corresponding to a 0.223% deviation from the CODATA Planck length 1.616255×10⁻³⁵ m. The result is therefore not a gravitational definition of the Planck scale but a structural emergence of a Planck‑scale UV cutoff implied by BRISM’s internal geometry together with empirical infrared input.All BRISM papers on Zenodo >> Searchlist
Swen Carlo Heinze (Tue,) studied this question.