adolescenceChildhoodRatio
plain-language theorem explainer
adolescenceChildhoodRatio defines the ratio of adolescence to childhood age boundaries as 20/12. Anthropologists and Recognition Science researchers would cite this constant when checking the predicted five-grade structure against ethnographic data. The declaration is a direct real-number assignment with no computation or lemmas.
Claim. The ratio of the upper boundary of adolescence to the upper boundary of childhood is defined as $20/12$.
background
The module shows that human societies recognize five age grades, a count forced by configDim D = 5. Adjacent grade boundaries scale near φ, with childhood ending at 12 years and adolescence at 20 years. This supplies the explicit ratio adolescenceChildhoodRatio as the scaling factor between those intervals.
proof idea
The declaration is a direct definition that assigns the constant value 20/12.
why it matters
This definition supplies the concrete ratio used in AgeGradingCert to certify the five-grade structure together with the bound |ratio - φ| < 0.1. It instantiates the RS prediction that life-span ratios scale near φ, linking the anthropological pattern to the forcing chain where φ is the self-similar fixed point. The parent structure AgeGradingCert packages the ratio with the grade count to form a verifiable certificate.
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