How statement and proof provenance work
The first chip identifies the source of the statement or construction; the second identifies the source of its local proof or verification.
- Literature-sourced: the exact statement appears in a cited source; only wording and notation differ.
- AI-adapted: a semantically identical restatement of literature-sourced material, modulo indexing, notation, and boundary cases adopted by the library.
- AI-generated: a genuinely novel statement formulated by AI, with no source for the claim itself.
These labels describe origin, not correctness: citations and verification chips remain separate evidence.
Flat complex torus: canonical triviality and non-full SU(n) holonomy for n ≥ 2
Example
Assume full AC. Let , let be a full lattice generated by a real basis of , and put . The standard Euclidean Hermitian metric descends, with real fundamental form . Then is a compact connected Kähler manifold and its canonical bundle is trivialized by the descended nowhere-zero holomorphic form . Let be the Levi-Civita connection of the descended metric and define its curvature by . The metric is flat when ; in this example it is flat and has trivial holonomy. For , trivial holonomy is a proper subgroup of , so the broad Calabi–Yau convention does not force exact holonomy. For , is itself trivial and this example does not separate the groups.
Example references
Facts & Assumptions
Given: Full AC; a real basis of ; the standard complex structure and Euclidean metric; and the broad convention from the preceding item.
Full AC is the choice-function principle of The Axiom of Choice and is inherited from the complete convention supplier.
The broad convention requires a connected compact Kähler -fold with a specified holomorphic trivialization of its canonical line bundle; it adds no holonomy equality assumption (Compact Calabi–Yau manifold conventions).
For a supplied smooth Riemannian metric the Levi-Civita connection is the unique torsion-free, metric-compatible connection; parallel transport is defined by parallel sections, and holonomy is generated by transports around based loops (Compact Calabi–Yau manifold conventions).
Verification
The real-linear isomorphism sending the standard basis to maps onto , so is discrete; bounded sets meet finitely because their inverse images under are bounded and bounded sets meet finitely. For every compact , if then , a bounded set meeting the lattice finitely; this proves proper discontinuity, and freeness follows because a translation fixing a point has vector . The shortest nonzero lattice length is positive. Distinct orbits have positive distance: for fixed representatives , only finitely many can satisfy for any fixed , so if no the minimum distance is positive. Small disjoint balls therefore separate distinct orbits and give Hausdorff quotient charts; choosing their radii below half the shortest lattice length makes their nonidentity translates disjoint. The chart transitions are translations and therefore holomorphic. The closed fundamental parallelepiped is compact and surjects onto , proving compactness; the quotient map is continuous and surjective, proving connectedness.
Translations preserve , , and , so these descend. The descended is real, positive, and closed, hence Kähler. Translations also preserve ; it descends to a nowhere-zero holomorphic section of , which trivializes by the preceding convention [F1].
On , define for the constant real coordinate frame . Deck translations have identity differential, so this connection descends and the frame remains global and parallel. The fields commute, giving ; torsion is tensorial, so . Since is constant and , the connection is metric-compatible, hence is Levi-Civita by [F2]. Its curvature annihilates each parallel , and since these form a frame, . Along any piecewise smooth loop, a parallel field has constant coefficients in this global frame, so its endpoint equals its initial value; the holonomy group is trivial.
For , choose . The matrix is unitary, has determinant , and is not the identity; hence is nontrivial and cannot equal the trivial holonomy group. For , , as stated.