EL Science — Volume II The Gravitational Sector, Structure Growth, and the Minimal Anisotropic-Stress Signature

This volume extends EL Science from background cosmology into the gravitational and structure-growth sector while fully retaining General Relativity with fixed G. The framework introduces a conserved vacuum stress-energy sector sourced by the evolving internal vacuum state variables (C, R, Ψ, K, V), allowing ΛCDM to emerge naturally as the stable-vacuum limit. A structured deterioration sequence is formulated to unify the present accelerated-expansion epoch with the future compression-dominated collapse phase as ordered stages of a single vacuum-evolution process. The perfect-fluid baseline is tested against cosmic structure growth using redshift-space-distortion fσ8 measurements, BAO distances, and expansion-history consistency checks, showing near-degeneracy with ΛCDM while correctly predicting the absence of significant σ8 tension relief at the smooth-dark-energy level. The volume then introduces the framework’s minimal anisotropic-stress formulation, generating a gravitational-slip and lensing-growth split whose present-day amplitude is naturally suppressed by the still-healthy vacuum state. The resulting signature remains below current detectability while increasing progressively as vacuum support deteriorates through cosmic evolution. This work establishes the gravitational architecture of EL Science, defines the framework’s tensor structure, presents its observational confrontations and limitations transparently, and identifies the open frontier linking the stable cosmological regime to the terminal avalanche-collapse dynamics explored in later volumes.