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.
Duplicate sites make the kernel Gram matrix singular
Example
Let be any radial kernel, and let a site list contain .
Facts & Assumptions
Given: A radial kernel and a finite site list with .
A radial kernel has Gram entries , and ordinary RBF interpolation is defined on distinct sites. (Radial kernels, polynomial augmentation, and site geometry)
Verification
For every row index , the equal sites give . Thus the first two columns, and by symmetry the first two rows, coincide.
The nonzero vector is therefore in the nullspace of the Gram matrix, so the matrix is singular. This example violates the distinct-site hypothesis in [F1] and is not a counterexample to the interpolation theorem.
Depends on
Used by
Nothing in the library uses this result yet.
Dependency tree · one level
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Sources
- Narcowich, Ward, and Wendland, Sobolev bounds on functions with scattered zeros, Math. Comp. 74 (2005), §1 (standard reference, not scraped)