SFM 2.1 and the End of the Universe: Cosmic Fate, Continuation Failure, and Descriptive Admissibility at Final Scale

This paper applies SFM 2.1 to proposed cosmic end-state scenarios, including heat death, big rip, big crunch, vacuum decay, black-hole evaporation futures, and unknown final regimes. It does not claim to predict the final fate of the universe, extend the physical life of the universe, or replace cosmology, general relativity, thermodynamics, quantum field theory, or existing physical models. Instead, it asks what kinds of continuation, description, and meaning remain admissible when the structural conditions required for events, observers, relations, matter, time-order, and persistence are progressively exhausted. The paper treats cosmic endings as continuation-boundary conditions rather than merely final events. Each proposed end-state is analysed according to what persists, what locks the transition, what descriptions remain admissible, what continuity geometry remains possible, and what traversal can still proceed. Core proposition: Before asking how the universe ends, we must ask what kinds of continuation remain admissible as the conditions required for structure, relation, time-order, matter, observation, and persistence are exhausted.