Kerr Geometry and the Angular-Duality Wavelength: Mass Cancellation and Borderline Resonance from Nanoparticle to Galaxy - version 1

Important note for readers of Version 1: This is the original Version 1. A revised Version 2 DOI: 10.5281/zenodo.19275058 has been uploaded with a clarified title, improved abstract, clearer logical flow in the Mass Cancellation Theorem, and an updated borderline section with tungsten and graphene nanoparticle calculations. In both versions the angular-duality wavelength λ_ad ≡ J/(M c) is introduced as a purely geometric, mass-independent scale. The collective de Broglie wavelength λ_dB = h/(M v) is a separate quantum quantity. These two lengths are not equal in general. Equality holds only along a specific borderline in (J, v)-space — an exceptional resonance condition that is not claimed as a universal identity. We recommend reading Version 2 for the most precise presentation https://zenodo.org/records/19275058 Full A-series are available in A9 description https://zenodo.org/records/18888582