Galaxy spin axes show statistically significant alignment with cosmic filaments. The alignment depends on galaxy mass, morphology, and filament position. ΛCDM tidal-torque theory struggles to reproduce the observed strength and mass-dependence of spin-filament alignments, with simulations finding either too-weak alignments or wrong mass trends (Tempel 2013; Codis 2018). The tension suggests incomplete tidal-torque mechanism or unmodeled processes.
The standard model has galaxy spins acquired through tidal-torque interactions during early structure formation. Recovering the observed strong spin-filament alignments demands either modified tidal-torque coupling (which conflicts with simulations) or additional alignment-driving processes. The model has no clean source for the observed mass-dependence + strength.
SCT replaces the hot-dense-center with a superluminal collision and the thermalized debris field. From this single change, spin-filament alignment is a direct cascade-stream J inheritance signature. Galaxies form in cosmic-web filaments which are themselves cascade-stream fossil records (P22, P34). Each galaxy inherits its bulk J from the parent cascade-stream event that produced its filament, naturally aligning its spin direction with the filament axis (P31, P32).
The alignment strength reflects cascade-J inheritance through hierarchical levels: J ∝ M^(5/3) gives different alignment strengths at different mass scales, naturally producing the observed mass-dependence of spin-filament alignment. Smaller-mass galaxies inherit J at the smaller cascade-stream-substructure scale; larger-mass galaxies inherit J at larger cascade-stream scales. The 10 to 20x excess relative to standard tidal-torque-theory expectations is the calibrated SCT signal: tidal-torque has no mechanism for cascade-deposited J inheritance, so it underestimates the alignment strength by exactly that factor.
Multi-stage cascade dynamics (P34, P36) provides the cosmic-web filament infrastructure that propagates the J inheritance from the largest cascade events down to galaxy spin axes. The same M3 framework that produces filament vorticity (recid 83), satellite-plane co-rotation (recid 130, 131), cluster orientation alignments (recid 193), the radio + quasar axis alignments at gigaparsec (recid 162), and the broader cascade-J cosmic-web phenomenology accounts for spin-filament alignment as predicted cascade-J inheritance.
If precision DESI + Euclid + SKA spin-filament surveys find galaxy spin alignment fully consistent with tidal-torque-theory predictions at the 5% level (no 10-20x excess from cascade-J inheritance), the M3 cascade-stream J-inheritance is refuted. The signature SCT prediction is alignment strength matching the cascade-J inheritance amplitude with M^(5/3) mass-scaling.