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The centered maximal operator is bounded on for
Statement
Assume the Axiom of Countable Choice (The Axiom of Countable Choice ()).
Let . Then there is a constant such that every satisfies By comparison, the same is true for the uncentered maximal function.
Facts & Assumptions
Given: The Axiom of Countable Choice, an exponent , and a function .
The centered maximal operator is of weak type with constant . (The centered Hardy-Littlewood maximal operator is weak type )
The centered maximal operator is of strong type with operator norm at most . (The centered maximal operator is bounded on )
A sublinear operator of weak type and strong type is of strong type for every . (Marcinkiewicz interpolation from weak and strong )
One has pointwise. (The centered and uncentered maximal functions are pointwise comparable)
Proof
The maximal operator is sublinear by definition of supremum and absolute [L1, L2, L3, given, algebra] values. Apply [L3] with the constants from [L1] and [L2]. This yields a constant such that
Step 1.1 proves the centered estimate. Then [L4] gives [step 1.1, L4, algebra] so the uncentered estimate follows as well.
Depends on
- The Axiom of Countable Choice ($\mathrm{AC}_\omega$)
- The centered and uncentered maximal functions are pointwise comparable
- The centered maximal operator is bounded on $L^\infty$
- The centered Hardy-Littlewood maximal operator is weak type $(1,1)$
- Marcinkiewicz interpolation from weak $(1,1)$ and strong $(\infty,\infty)$
Used by
Nothing in the library uses this result yet.
Dependency tree · two levels
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Sources
- Gerald B. Folland, Real Analysis: Modern Techniques and Their Applications, 2nd ed., Corollary 6.35 (standard reference, not scraped)
- G. H. Hardy and J. E. Littlewood, A maximal theorem with function-theoretic applications, Theorem 13 (standard reference, not scraped)