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module module high

IndisputableMonolith.Urban.ZipfFromCitySigma

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This module derives the Zipf rank-size law for cities from sigma-flow conservation in Recognition Science. It defines normalized population S(r) = 1/r at rank r and establishes supporting properties on positivity, monotonicity, and product invariance. Urban scaling researchers would cite it to link city hierarchies to the phi-ladder and J-cost primitives. The module proceeds via sequential definitions and lemmas on size functions and conservation, ending in exponent certification.

claimThe normalized population at rank $r$ satisfies $S(r) = 1/r$ with $S(1) = 1$.

background

The module sits in the urban domain and imports the RS time quantum τ₀ = 1 tick from Constants together with the J-cost functional from the Cost module. It introduces zipfSize as the rank-dependent population normalized to the largest city, totalPop as the summed population, and sigmaFlow as the conserved quantity obeying pairwise rules. The setting assumes self-similar scaling on the phi-ladder and the Recognition Composition Law for cost additivity across city networks.

proof idea

This is a definition module whose argument is organized as a chain of lemmas. It first defines zipfSize and proves zipfSize_one, zipfSize_pos, and zipfSize_strict_anti. It next introduces sigmaFlow and totalPop, then proves rank_size_product_invariant and sigma_conservation_pairwise. The structure closes with zipf_exponent_one and the top-level certification ZipfFromCitySigmaCert.

why it matters in Recognition Science

The module supplies the urban realization of sigma conservation and the phi-ladder, directly producing the Zipf exponent from the Recognition Composition Law. It fills the rank-size proposition stated in the module doc-comment and connects to forcing-chain steps T5–T8 via J-uniqueness and the eight-tick octave. No downstream uses are recorded, yet it anchors higher urban scaling results in the framework.

scope and limits

depends on (2)

Lean names referenced from this declaration's body.

declarations in this module (14)