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.
The average of a locally integrable function over a Euclidean ball
Definition
Assume the Axiom of Countable Choice (The Axiom of Countable Choice ()).
Let (A locally integrable function on ), let , and let . The ball average of over is
The denominator is well defined because Euclidean balls have positive finite Lebesgue measure shows that every Euclidean ball has positive finite Lebesgue measure.
Depends on
Used by
- One centred ball-mean identity does not force harmonicity Counterexample
- Poincare-Wirtinger fails on disconnected bounded domains Counterexample
- The Harnack estimate needs an additive forcing term Counterexample
- The Harnack inequality requires nonnegativity Counterexample
- Axis-parallel cubes, their averages, and cube maximal functions Definition
- Lebesgue points and the Lebesgue set of an L¹_loc class Definition
- Spherical averages and local ball means in Rn Definition
- Spherical means and the weighted ball integral of space-dependent data Definition
- The centered and uncentered Hardy-Littlewood maximal functions Definition
- A locally integrable function can fail to differentiate on a null set Example
- Hilbert transform of the line Poisson kernel Example
- Piecewise-affine approximation of a measurable coefficient Example
- Worked oscillation decay and its Hölder modulus Example
- A finite interior ball chain propagates weak Harnack bounds Lemma
- Ball means and sphere means are related by a radial derivative Lemma
- Ball-mean oscillation bound by the Riesz potential of the gradient Lemma
- Continuous compactly supported functions are recovered by small ball averages Lemma
- De Giorgi oscillation reduction: one half-level set is small Lemma
- Geometric oscillation decay implies a Hölder modulus Lemma
- Moser iteration for positive supersolutions: negative-power and logarithmic comparison Lemma
- Sobolev level-set step: energy decay with explicit level gap and radius loss Lemma
- The Euler–Poisson–Darboux equation for spherical means Lemma
- Zero-set propagation for a nonnegative Holder weak solution Lemma
- Ball averages vary continuously with the centre and radius Proposition
- De Giorgi local boundedness of homogeneous subsolutions Theorem
- De Giorgi-Nash interior Holder regularity for divergence-form equations Theorem
- Harnack inequality for nonnegative weak solutions Theorem
- Interior Schauder estimate for uniformly elliptic equations Theorem
- Lebesgue differentiation theorem on ℝⁿ Theorem
- Morrey's inequality for p>n Theorem
- Poincare inequality on a ball Theorem
- The mean-zero Poincare inequality on bounded John domains Theorem
- The Poincare inequality with a positive-measure zero set Theorem
- W^1,∞ functions on convex domains have Lipschitz representatives Theorem
- Weak Harnack inequality for nonnegative supersolutions Theorem
Dependency tree · two levels
17 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
- Gerald B. Folland, Real Analysis: Modern Techniques and Their Applications, 2nd ed., Section 3.4 (standard reference, not scraped)