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IndisputableMonolith.Chemistry.CrystalSymmetry

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This module defines the allowed rotation orders and crystallographic predicates in the Recognition Science framework. Researchers modeling crystal lattices from eight-tick coordination would cite it to constrain symmetry groups. The module supplies definitions and theorems establishing exactly five permitted orders, importing the CrystalStructure and Constants modules.

claimThe allowed rotation orders form the finite set $\{1,2,3,4,6\}$ of positive integers $n$ for which a $2\pi/n$ rotation preserves lattice periodicity; the predicate isCrystallographic holds precisely on this set.

background

The upstream CrystalStructure module derives BCC, FCC, and HCP lattices from RS principles, with BCC coordination number 8 reflecting the eight-tick ledger period. Constants supplies the RS time quantum $\tau_0 = 1$ tick. The present module extends these to symmetry by introducing allowedRotationOrders together with predicates that filter rotation orders compatible with periodic boundary conditions.

proof idea

This is a definition module, no proofs.

why it matters in Recognition Science

The module supplies the symmetry filter required for the CrystalSystem and numPointGroups definitions that appear among its siblings. It therefore supports the classification of crystal structures already shown to emerge from the eight-tick coordination mechanism in the CrystalStructure module.

scope and limits

depends on (2)

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declarations in this module (35)