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Equivariant cube roots on three primitive lift orbits

Abstract

The complete original histories over three disjoint primitive base orbits admit precisely local cube roots or a compatible three-cycle.

Definition 1.1 (All original histories over the three signed base orbits).

Formalization. D5/S3/ConceptDynamics/Coding/PrimitiveLifts/ThreeOrbitCubeRootCriterion.OrbitUnion (✓ std3).

Source. Repository-derived.

Commentary.

OrbitUnion C P Q S contains every original bilateral legal history of expandedGraph C whose forgotten numbered-edge history is an integer translate of P, Q or S. All phases and group coordinates remain present.

Definition 1.2 (The restricted original time shift).

Formalization. D5/S3/ConceptDynamics/Coding/PrimitiveLifts/ThreeOrbitCubeRootCriterion.unionShift (✓ std3).

Source. Repository-derived.

Commentary.

The time map is exactly the original one-step shift on each underlying history. An integer base phase t becomes t+1.

Definition 1.3 (The original deck action on the full union).

Formalization. D5/S3/ConceptDynamics/Coding/PrimitiveLifts/ThreeOrbitCubeRootCriterion.unionDeck (✓ std3).

Source. Repository-derived.

Commentary.

The left action of a is the original groupHistory C a. It preserves the forgotten numbered-edge history. No finiteness or commutativity assumption is imposed on H.

Theorem 1.4 (Complete three-orbit cube-root criterion).

Proof. Machine-checked in Lean as D5/S3/ConceptDynamics/Coding/PrimitiveLifts/ThreeOrbitCubeRootCriterion.cube_root_criterion (✓ std3). ∎

Source. Repository-derived.

Commentary.

Let d,e,f be the positive minimal periods of P,Q,S, whose signed base orbits are pairwise disjoint. A deck-equivariant endomap R of the entire original-history union cubes to the original shift exactly when the three local signed cube-root equations all hold, or d=e=f and consecutive ordered holonomies admit intertwiners bhQ=hPb and chS=hQc. Each local equation has s:Fin d, m:Int and b:H with Commute b h, 3s.val=1+dm and b^3*h^m=1, and independently for the other components. No preservation of components, time commutation or bijectivity is assumed of R.

The three signed base-orbit hypotheses identify the disjoint union of the complete actual lift atlases with this full history subtype. The equivalence keeps the very same underlying numbered-edge history, intertwines every original deck operation and intertwines the original time shift. Conjugating an arbitrary root through it gives precisely the three-chart cube-root problem, rather than a root on selected representatives or a reduced fibre.

The atlas criterion extracts the induced action on three components. A cube root either preserves them all or permutes them in a three-cycle. In the latter case cyclic seam divisibility forces the three primitive periods to be equal, and the ordered seam equations force the displayed conjugacies. Compatible transports then construct a root with one time step on the closing arrow. The order in these group equations is retained; equal holonomy orders or equal ordinary periodic counts are insufficient substitutes. The result concerns these three signed base orbits and does not claim a classification for an arbitrary number of components or literature priority.

References