We present a cosmological implementation in which the dark sector emerges as an environment-dependent geometric residual of spacetime torsion within the Einstein–Cartan–Sciama–Kibble framework. Torsion is algebraic and non-propagating, remaining inactive throughout the early Universe and preserving standard calibration (CMB, BAO, sound horizon), while becoming relevant only in virialized environments at late times. Using a fixed, cluster-calibrated environmental backbone implemented in a modified CLASS solver, we confront late-time expansion and growth observables without parameter re-optimization. The framework accommodates a high local H₀, yields a consistent cosmic age, and predicts suppressed growth on weak-lensing scales. A key falsifiable prediction is an environment-dependent modulation of the inferred Hubble constant, providing a direct test for upcoming surveys.
Alejandro Rey (Thu,) studied this question.