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IndisputableMonolith.Aesthetics.SymmetryGroupPreference

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The module enumerates the seventeen wallpaper groups in IUC notation and supplies supporting functions for orbit counts and symmetry ratios. Researchers in pattern aesthetics or crystallographic symmetry would cite the standardized list when quantifying preference via J-cost. The module is purely definitional and imports only the time quantum from Constants together with cost primitives.

claimThe set of seventeen wallpaper groups in IUC notation, ordered as in Schattschneider 1978, together with the functions orbitCount : WallpaperGroup → ℕ and symmetryRatio : WallpaperGroup → ℝ that measure orbit structure and symmetry density.

background

The module sits in the Aesthetics domain and imports the RS time quantum τ₀ = 1 tick from Constants and the cost machinery from Cost. WallpaperGroup is defined as an inductive enumeration of the seventeen plane symmetry groups; orbitCount returns the number of distinct orbits under the group action on the plane, while symmetryRatio normalizes this count to a value in (0,1]. These definitions prepare symmetry data for later J-cost comparisons.

proof idea

This is a definition module, no proofs.

why it matters in Recognition Science

The module supplies the canonical list of wallpaper groups required for any downstream symmetry-preference metric. It directly supports the definitions of symmetryRatio and wallpaperJ that appear among its siblings, providing the enumeration step needed before J-cost or phi-ladder comparisons can be applied to aesthetic patterns.

scope and limits

depends on (2)

Lean names referenced from this declaration's body.

declarations in this module (25)