Formalizes seventeen photochemical and photophysical theories and all pairwise relations among them in Lean 4 over a shared kernel, with machine-checked iff adjudications.
Abstract
Chemistry's phenomenological theories multiply with its observables: the same physical reality is repeatedly named in different measurement contexts, and the relations among theories have never had an auditable carrier. Here we present PhotoLean, a machine-checked genealogy of seventeen photochemical and photophysical theories formalized in Lean 4 over a shared kernel. Every pair of theories carries either a verified relation (equivalence, implication, composition with registered premises, definitional certificate) or a registered reason for its absence, covering all 136 pairs. Three adjudications resolve inherited conflations with if-and-only-if boundaries and witnesses: the symmetry factor $β$ equals one-half exactly when reactant and product force constants coincide; Kasha's rule and the Kasha-Vavilov rule agree only under closed quantification with a loss channel; and intensity-only Stern-Volmer data cannot distinguish static from dynamic quenching, whereas the lifetime channel discriminates exactly. As proposition generation shifts to machines, such machine-checked relational ledgers offer a replicable audit layer for theory itself.
Problem
Chemistry's phenomenological theories multiply with its observables. The relations among these theories (equivalence, implication, conflation) have no auditable carrier and live only in textbooks and tacit consensus.
Approach
PhotoLean is a Lean 4 development that formalizes seventeen photochemical and photophysical theories over a shared kernel. The kernel is an equal-curvature two-parabola object. Every one of the 136 theory pairs receives either a verified relation (equivalence, implication, composition with registered premises, or definitional certificate) or a registered reason for its absence. The corpus is calibrated with fidelity probes, rfl kernel certificates against definition drift, axiom audits, and a strict gate check.
Figure 1: The PhotoLean relation graph: seventeen photochemical/photophysical theories on one machine-checked graph. Nodes are the seventeen delivered theories plus the shared kernel (white); the number inside each node is its count of statement-authority declarations (total 1153, all delivered verbatim; 17/17 fidelity probes report zero signature differences), and node size scales with that count
Results
All 1,153 statement-authority declarations are delivered verbatim, with 17/17 fidelity probes passing and full edge coverage. Three adjudications are proved as iff boundaries with witnesses on both sides. The symmetry factor β = 1/2 holds exactly when the force constants are equal. Kasha's rule and the Kasha–Vavilov rule coincide only under closed quantification with a loss channel. Intensity-only Stern–Volmer data cannot separate static from dynamic quenching, while the lifetime channel can.
Figure 2: Three adjudication classes: literature conflations decided with machine-checked boundaries. a , A1 , adjudicated conflation of the symmetry factor \beta=1/2 . The colour map displays the thermoneutral crossing coordinate x^{*}=\sqrt{k_{p}}/(\sqrt{k_{r}}+\sqrt{k_{p}}) over the force-constant plane (k_{r},k_{p}) ; this closed form is unique on [0,1] and is obtained without calculus. The coFigure 3: Delivery scale, edge-inventory composition, and verification gates. Left: the statement-authority footprint of each theory (1,153 declarations spanning 92 theory modules; 1,214 public delivered declarations; every authority statement delivered verbatim with zero probe discrepancies), coloured by family. Right: the composition of the 78 declarations that constitute the machine-checked edg