A Structural Aether Cosmology: A Proof-of-Concept for a Rotational Origin of the Dark Sector

We explore a conceptual cosmological framework, the Structural Aether Model. This theoryposits that the "Dark Sector" (Dark Matter and Dark Energy) may not consist of exotic particles ora cosmological constant, but could instead be a manifestation of a single, unified vector field, or"Aether" (𝑢μ). This field defines a preferred frame and possesses intrinsic vorticity (ωμν). Wedemonstrate that this model, when formalized in a covariant Lagrangian, appears capable ofresolving the primary phenomenological challenges facing such a theory. We first establish thesevere observational constraints from the Cosmic Microwave Background (CMB), which limitsany simple, global rotation to 𝑣/𝑐 ≲ 10−5, suggesting a scale-dependent formulation is required.We then derive an "Aether-Lorentz Force" (𝐹 ∝ ω ⋅ 𝑣) which acts as a candidate mechanism forModified Newtonian Dynamics (MOND). We demonstrate, via 1D and static numericalsimulations, that this force: (1) admits solutions that reproduce the qualitatively flat rotation curvesof spiral galaxies, and (2) exhibits collisionless-like dynamics in "toy model" cluster collisionscenarios. We then show that the Aether field's equation of state, in its simplest form, is 𝑤 =−1/3, identical to Cosmic Curvature. By introducing a self-interaction Potential (𝑉(ω)), weconstruct a "chameleon" model that transitions from a matter-and-curvature-dominated era to apotential-dominated "Dark Energy" era (𝑤 → −1). Finally, we demonstrate that a hypotheticalphase transition in this potential can trigger a cosmological re-collapse, providing a consistentmechanism for a "Timeless Infinity" end-state.