theta13_degrees
plain-language theorem explainer
The definition assigns the reactor neutrino mixing angle θ₁₃ the numerical value 8.57 degrees. Neutrino model builders working in Recognition Science cite this constant when populating the best-fit PMNS parameter record. It is implemented as a direct numerical assignment with no derivation steps or logical reductions.
Claim. The reactor neutrino mixing angle satisfies θ₁₃ = 8.57°.
background
The PMNSMatrix module develops the Pontecorvo-Maki-Nakagawa-Sakata matrix for neutrino flavor mixing from Recognition Science, where angles are expected to follow φ-quantized patterns. The three mixing angles are the solar θ₁₂, the near-maximal atmospheric θ₂₃, and the reactor θ₁₃, with the module noting large mixing unlike the CKM sector and suggesting golden ratio geometry. This supplies the observed reactor angle to match sin²θ₁₃ ≈ 0.0220 for the bestFitPMNS construction.
proof idea
The declaration is a direct numerical definition. No lemmas are applied and no tactics are used.
why it matters
It supplies the theta13 field required by bestFitPMNS to assemble the full PMNSParameters record. The entry advances the SM-014 target of deriving the PMNS matrix from φ-angles in the Recognition framework, anchoring the small reactor sector consistent with the phi-ladder and eight-tick octave structures.
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