SU(2) as Torsional Transaction

This paper develops the SU(2) sector within Infratier Closure Physics as the torsional transaction layer between U(1) dispersive curvature storage and SU(3) confinement closure. In the Standard Model, SU(2) appears as the gauge symmetry associated with weak interaction and electroweak dynamics. In the present framework, this gauge structure is interpreted as the empirical expression of a deeper closure regime: the infratier layer in which curvature is no longer merely radiative or phase-preserving, yet has not entered the full confinement regime characteristic of SU(3). SU(2) is therefore understood as the geometry of mediated transformation. It is the layer where curvature becomes torsional, chirality becomes structurally active, and particle identity becomes transactable. On this interpretation, weak interaction phenomena–including beta decay, neutrino participation, chirality selection, W/Z mediation, and particle transmutation–are not isolated empirical features but expressions of a common torsional transaction principle. The weak interaction is weak only from the external 3.0D perspective; ontologically, it marks the capacity of the physical system to cross identity states through mediated closure. This paper situates SU(2) within the infratier sequence and clarifies its role as the necessary middle term between electromagnetic dispersion and chromodynamic confinement.