VSL-Q: A Thermodynamic Cosmological Framework with Inflation-like Dynamics, Emergent Dark Energy, and Effective Galactic Phenomenology

This release presents an expanded and revised version of the VSL-Q framework, an effective thermodynamic approach to cosmology based on vacuum–matter energy exchange and horizon thermodynamics. The framework provides a unified macroscopic description of three sectors: (i) an early-time inflation-like causal regime without an inflaton field, (ii) late-time cosmic acceleration arising from continuous vacuum–matter coupling, and (iii) effective weak-field galactic phenomenology consistent with asymptotically flat rotation curves. In the deep low-acceleration limit, the baryonic Tully–Fisher relation emerges naturally as a consequence of the effective dynamics rather than being imposed as an empirical input. For late-time acceleration, the background expansion history is specified in closed analytic form, and an effective equation of state can be reconstructed as a derived diagnostic quantity. The framework emphasizes internal consistency, parameter economy, and falsifiability: closed sectors, partially constrained sectors, and intentionally open sectors are explicitly delineated in the accompanying status summary. This version supersedes earlier preliminary releases associated with this record and should be considered the primary reference for the current state of the framework. Contents include the complete technical document set (chapters and appendices), including an exploratory appendix on the intermediate-acceleration galactic regime.