Skewed lensing shear statistics: Vorticity contributes to the imaginary component of the lensing potential, introducing directional lensing distortion.
Time delay asymmetries: Torsion affects the Shapiro delay, especially in strong lensing systems aligned with cosmic vorticity axes.
Lensing B-modes: While usually associated with tensor modes, residual rotation may generate small B-mode polarization contributions in weak lensing shear patterns.
These distortions can be constrained using surveys like LSST and Euclid, which offer the resolution and sky coverage necessary to detect such subtle signals.
5.4 Testable Predictions for Upcoming Surveys
The model presented makes several distinctive predictions that can be tested or constrained using next-generation cosmological observations:
Moreover, by constraining the spin-torsion coupling parameter \alpha, it is possible to place limits on early-universe spin density and its influence on large-scale structure.
Summary
The Einstein--Cartan--Bianchi IX cosmology provides a fertile ground for addressing existing anomalies in observational cosmology. It delivers:
A natural explanation for CMB anomalies,
Subtle but testable deviations in BAO and SN observations,
