Update (February 2026): This record now includes a Technical Note (Technical Note - Conceptual Clarification and Geometric Differentiation of GUFT.pdf). This supplementary document specifies the theoretical foundations of GUFT in contrast to recent phenomenological models. It clarifies the distinction between the geometric viscosity proposed here (based on Kelvin-Voigt transport derivatives and baryon-density dependence) and other approaches relying on ad-hoc elastic constants or additive tensors. Original Abstract: This dossier presents the Geometric Unified Framework Thesis (GUFT), an alternative to standard cosmology (ΛCDM) that dispenses with dark components (Dark Energy and Dark Matter) through a strict application of General Relativity in non-linear regimes. The central thesis postulates that spacetime is not a passive background, but a dynamic medium exhibiting an effective geometric viscosity. Modeling the vacuum under a constitutive principle analogous to the Kelvin-Voigt model (see Appendix A), we demonstrate that curvature possesses inertia and historical memory. Within this framework: "Dark Energy" is reinterpreted as an artifact of differential time dilation in a non-homogeneous universe dominated by cosmic voids. "Dark Matter" naturally emerges as gravitational hysteresis: the memory of curvature accumulated by rotational dynamics in a medium with a non-zero relaxation time (τ > 0). GUFT offers a parsimonious solution that restores locality and physical realism, eliminating the need for arbitrary constants and resolving critical observational tensions such as the Bullet Cluster and the Hubble Tension, without invoking new physics beyond the geometry of spacetime.
Xavi Barrera (2026) studied this question.