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.
Explicit polynomial time constant degree expanders exist
Statement
There is a uniform polynomial-time algorithm producing, for each positive vertex count , a degree- expander with absolute nontrivial norm at most . The output has adjacency slots; its bit-time cost is polynomial in .
Facts & Assumptions
Given: the objects and hypotheses in the statement above.
For every integer there is a polynomial-time constructible reverse-paired -regular multigraph on exactly vertices with For every satisfies . Every vertex has loops. (Expander size adjustment and laziness).
Proof
Apply the all-size construction at the given . Its bound is independent of and is strictly smaller than one. For its unnormalized expansion is at least , so normalized expansion is at least .
The construction explicitly lists destinations at each of the vertices and runs in polynomial bit time. The singleton output has only loops and satisfies the zero-space spectral convention. Endpoint names require logarithmically many bits, so the adjacency-slot count alone is not a claim of linear bit time.
Depends on
Used by
- Nonconstructive expanders suffice for uniform reductions False statement
Dependency tree · two levels
3 results within two dependency steps of this one, each drawn at its shortest distance from it. An arrow runs from a result to what uses it, so the chart reads left to right and ends at this result, which carries a heavier outline. Every node is a link to that result. Click elsewhere on the chart to enlarge it.
Sources
- Irit Dinur, The PCP theorem by gap amplification; §2.1 Lemma2.1, p8, instantiated by preceding construction. (standard reference, not scraped)