El Science Volume 2: A Cyclic Lifespan Cosmology with Vacuum Collapse and Gravitational Phase Transition

This paper presents El Science Volume 2: a cyclic cosmological framework grounded in structural realism, in which the universe's evolution is governed by an asymmetric structural form rather than by the dynamics of any single physical mechanism. The form consists of a fast onset, a decelerating development, an apparent-stability phase, a peak that functions as the structural pivot from existence-mechanics to death-mechanics, and an asymmetric decline terminating in a snowball compression. The cycle closes at a convergence-point — a geometric boundary, not a configuration — where the death of one cycle is simultaneously the birth of the next. Two physical mechanisms are proposed to instantiate the form within a cycle: vacuum collapse drives the terminal snowball compression, and a gravitational phase transition at a specific (currently unknown) threshold value handles the convergence. The framework reproduces all standard observational cosmology in the past — by construction, the lifespan factor L(τ) reduces to unity in the matter-dominated era, leaving ΛCDM untouched. It diverges from ΛCDM in the deep future, where it predicts an eventual end of expansion through vacuum-driven dissolution rather than eternal de Sitter behavior. The framework has been empirically tested against the full Pantheon+ supernova release (1580 supernovae with full statistical and systematic covariance). El Science Cyclic produced χ² = 1386.76 versus 1387.94 for ΛCDM — a marginal raw-χ² improvement that does not survive Bayesian Information Criterion penalty. The data is consistent with both models. Crucially, this null result is consistent with El Science's own prediction that L(τ) ≈ 1 throughout the supernova-accessible redshift range, well before the framework's predicted snowball regime. The framework is offered as exploratory, not final. We adopt the methodological posture that structural form is primary and physical materials serve the demonstration of the form. We name openly the deferred questions: the form's own origin, the precise threshold value of the gravitational phase transition, and the mechanism by which the post-convergence phase establishes smoothness and low entropy. Volume 1 (foundational): https://zenodo.org/records/17677270