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.
Closed target constraints survive compact extraction
Statement
Assume Countable and Dependent Choice. Let be a normed space with compact continuous inclusion , , and let be closed in norm. Every bounded sequence with admits a subsequence in with . In particular this applies to any of this page's Rellich inclusions, with their stated domain, exponent and choice hypotheses. This statement does not assert that belongs to or that is weakly closed.
Facts & Assumptions
Given: Countable and Dependent Choice, a normed space with compact continuous inclusion , a norm-closed set , and a bounded sequence in with for all .
The sequential form of a compact embedding. Under Countable and Dependent Choice, a compact continuous inclusion sends every bounded sequence in to a sequence with a subsequence converging in . (Compactly embedded normed spaces)
Closed sets contain sequential limits. A closed subset of a metric space contains the limit of every convergent sequence of its points: otherwise the open complement contains a ball about the limit, contradicting eventual membership of the sequence in that ball. (The metric topology: a set is open when every one of its points has a ball around it inside the set; closed means open complement, Topology on a set, open and closed sets, clopen sets, the closed-set axiomatisation, and the coarser/finer comparison, The closure of a nonempty is , equals together with its limit points, and is the smallest closed superset)
Proof
By [F1] the bounded sequence has a subsequence converging in to some .
Since for every and is closed, [F2] gives ; the statement makes no claim that lies in the image of . Countable and Dependent Choice are used exactly through the compact-embedding interface [F1].
Depends on
- Compactly embedded normed spaces
- The space $L^p(\mu)$ as the quotient by null functions
- The metric topology: a set is open when every one of its points has a ball around it inside the set; closed means open complement
- Topology on a set, open and closed sets, clopen sets, the closed-set axiomatisation, and the coarser/finer comparison
- The closure of a nonempty $A$ is $\{x : d(x,A) = 0\}$, equals $A$ together with its limit points, and is the smallest closed superset
- The Axiom of Countable Choice ($\mathrm{AC}_\omega$)
- The axiom of dependent choice: a relation in which every element is related to something admits an $\mathbb{N}$-indexed chain
Used by
Nothing in the library uses this result yet.
Dependency tree · two levels
38 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
- John K. Hunter, Notes on Partial Differential Equations, complete 242-page 2014 notes (standard reference, not scraped)