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.
A Bochner-integral forward map with weakly closed graph
Example
Assume the ultrafilter lemma, dependent choice, and HB. Give its full sigma-algebra and probability measure . For each , let be the simple function , , and define . With and the usual real Hilbert structure, is weakly closed and is nonlinear; if and , then , where weak convergence in means convergence under every bounded real-linear functional. For every , , its Tikhonov functional
has a global minimizer on .
Example references
Facts & Assumptions
Given: The ultrafilter lemma, DC, and HB; the finite set with ; the maps , ; and with the usual real Hilbert structure.
The ultrafilter lemma extends every filter to an ultrafilter (The ultrafilter extension principle (UL/BPI)).
DC supplies an infinite sequence following an everywhere-extendible relation (The axiom of dependent choice: a relation in which every element is related to something admits an -indexed chain).
HB is the real dominated-extension principle (The real dominated-extension principle as an additional hypothesis over ZF).
A measure is zero on the empty set and countably additive on disjoint measurable sets (Measures on sigma-algebras); a measure space consists of a set, sigma-algebra, and measure (Measure spaces).
A measurable simple Banach-valued function with finite-measure nonzero level sets is integrable and has integral (Banach-valued simple function and integral).
An integrable simple Banach-valued function is Bochner integrable, with its Bochner integral equal to the simple integral (Bochner-integrable function, The Banach-valued simple integral is well defined).
The real numbers with their standard inner product form a real Hilbert space (Real and complex inner-product spaces and their induced length, The reals are complete, Hilbert space).
Weak convergence in a normed space is convergence under every bounded real-linear functional (Weak convergence of nets and sequences).
The open-domain nonlinear forward-map interface permits any map on a nonempty norm-open set, without assuming linearity (Nonlinear forward maps between Hilbert spaces).
Under the assumptions of [A1]–[A3], a real-Hilbert weakly closed forward map on a nonempty weakly closed domain has a global minimizer for every positive parameter and datum (Existence of a global nonlinear Tikhonov minimizer).
The Tikhonov functional is on the domain (The nonlinear Tikhonov functional).
DC implies countable choice, the principle that every countable family of nonempty sets admits a choice function (Dependent choice implies countable choice, The Axiom of Countable Choice ()).
A weakly closed forward map has a weakly closed domain and sequentially weak-to-weak closed graph (Weakly closed nonlinear forward maps on Hilbert spaces).
Verification
The assignment is a measure: it is zero on , and any disjoint sequence of subsets of the two-point set has at most two nonempty members, so cardinalities, hence measures, add over the union. For , the two singleton level sets of have distinct nonzero coefficients and measure each. For , use the empty representation of the zero function; for , use . In all cases [F2] gives an integrable simple function with integral , and the constant approximating sequence in [F3] gives the same Bochner integral. Since , , and , it fails additivity and is nonlinear.
The domain is the entire weak topology space and is therefore weakly closed. If , [F5] applied to the identity functional gives in the usual real topology. The factorization shows , because convergence of makes the second factor bounded. If also , [F5] gives ; uniqueness of real limits yields . Thus the graph is sequentially weak-to-weak closed.
The domain is norm-open and nonempty, so [F6] confirms that this is also a forward map in the batch-25 open-domain convention. The graph and domain conditions just verified satisfy [F10]; with the real-Hilbert structure [F4] and axioms [A1]–[A3], they meet the hypotheses of [F7]. The DC-to-countable-choice consequence [F9] is the selection strength used in that theorem's proof. By [F8] this is the stated functional, so for every , it attains a global minimum.
Depends on
- Weakly closed nonlinear forward maps on Hilbert spaces
- The nonlinear Tikhonov functional
- Existence of a global nonlinear Tikhonov minimizer
- Nonlinear forward maps between Hilbert spaces
- Hilbert space
- Real and complex inner-product spaces and their induced length
- The reals are complete
- Weak convergence of nets and sequences
- The ultrafilter extension principle (UL/BPI)
- The axiom of dependent choice: a relation in which every element is related to something admits an $\mathbb{N}$-indexed chain
- The Axiom of Countable Choice ($\mathrm{AC}_\omega$)
- The real dominated-extension principle as an additional hypothesis over ZF
- Dependent choice implies countable choice
- Measure spaces
- Measures on sigma-algebras
- Banach space
- Banach-valued simple function and integral
- Bochner-integrable function
- The Banach-valued simple integral is well defined
Used by
Nothing in the library uses this result yet.
Dependency tree · two levels
76 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.