Geometric Reaction: From Quantum Hydrodynamics to a Cross-Domain Generative Principle

Geometric Reaction (First Law). Geometry is the operative container; any realized (above-threshold) difference within it induces a reaction R that unfolds as tempo T (time as rhythm of change) and residue M (persistent form, including matter). The recursive cycle geometry → reaction → new geometry appears across physics, biology, engineering, and narrative. From an action functional in density ρ and phase S, the framework yields a continuity equation and a Hamilton–Jacobi equation with a geometric information term Q[ρ,g]; under standard regularity (ρ > 0, phase single-valued up to 2πℏ) these recover the Schrödinger equation as an equivalent representation. Probabilities enter via the ensemble identification ρ = |ψ|² (not by derivation). The stance preserves causality and non-signalling and is compatible with PBR and Bell constraints. Randomness and infinity are treated as signals of incomplete mapping, not foundations. Universality is presented as a hypothesis, open to empirical and theoretical falsification via the stated counterexamples. In physics, this posture aligns with ongoing efforts to unify quantum mechanics and gravity; the schema is framed more generally and applies wherever geometry, difference, and reaction are well defined. In biology, this posture is consonant with ongoing work on the origin of life, reading prebiotic scenarios (energy gradients, compartmentalization, and cycles) through the same schema of geometry, difference, reaction, and residue. In cosmology, this posture is consonant with ongoing efforts on the cosmological constant problem, treating strictly uniform vacuum offsets as inert at the container level and reserving gravitating weight for reactive residues. Preprint; not peer-reviewed.