Dynamical Dark Energy from Axial Torsion–Scalar Mixing in Einstein–Cartan Cosmology: Gravastar Structure, Cyclic Reset, and Falsifiable Predictions

This is Version 2.0 of the Einstein–Cartan torsion dark energy framework. Building on the original “Source Code of the Universe” (Zenodo DOI: 10.5281/zenodo.19176816), this paper provides explicit derivations of the central mechanisms and four falsifiable predictions. The theory replaces the cosmological constant with a dynamical torsion energy density ρtor=ξϕ2σ2/a6ρtor=ξϕ2σ2/a6 arising from an axial torsion–scalar mixing term ξϕ2AμAμξϕ2AμAμ. The observable universe is modelled as a gravastar shell whose topological defects arrange into a Fibonacci spiral—the unique maximal-information packing on a sphere—saturating the holographic entropy bound. A cyclic reset occurs when torsion entropy reaches half the de Sitter horizon entropy, fixing ξ≈0.5ξ≈0.5 from first principles. Key results: Derivation of the tensor-to-scalar ratio 3×10−6≲r≲3.2×10−33×10−6≲r≲3.2×10−3 (testable by LiteBIRD). Neutron electric dipole moment drift ∣ddn/dt∣≲2.2×10−27 e⋅cm yr−1∣ddn/dt∣≲2.2×10−27e⋅cmyr−1 (testable by n2EDM and nEDM@SNS). Stochastic gravitational wave background at nHz with ΩGW∝f2/3ΩGW∝f2/3 (testable by IPTA). Hubble constant filament–void gradient ΔH0≈5 km s−1Mpc−1ΔH0≈5kms−1Mpc−1 (testable by DESI/Euclid). The central open parameter—the cosmic spin density σ0σ0—is identified explicitly, and three pending numerical calculations are listed. A transparent status table distinguishes derived results from those requiring further work. The philosophical interpretive layer (Six‑Path Architecture) is clearly separated and labeled non‑falsifiable. All four predictions are falsifiable before 2030; null results at the stated sensitivities would rule out the framework. The theory contains two free parameters, both fixed by theoretical consistency, and already matches multiple datasets (Planck, Pantheon+, SH0ES, NANOGrav) without post‑diction. This version corrects compilation errors present in the earlier draft and is fully compatible with revtex4‑2.