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arXiv · 1306.2653

Bellman approach to the one-sided bumping for weighted estimates of Calderón--Zygmund operators

Fedor Nazarov·Alexander Reznikov·Alexander Volberg
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Abstract

We give again (see also arXiv:1112.0676) a proof of weighted estimate of any Calderón-Zygmund operator. This is under a universal sharp sufficient condition that is weaker than the so-called bump condition. Bump conjecture was recently solved independently and simultaneously by A. Lerner (arXiv:1202.1860) and Nazarov--Reznikov-Treil-Volberg (arXiv:1202.2406). The latter paper uses the Bellman approach. Immediately a very natural and seemingly simple question arises how to strengthen the bump conjecture result by weakening its assumptions in a natural symmetric way. This is what we are dealing with here. However we meet an unexpected and, in our opinion, deep obstacle, that allows us to achieve only a partial result. The result of the present article is slightly stronger than the one in arXiv:1112.0676. Our proof consists of two main parts: reduction to a simple model operator, construction of Bellman function for estimating this simple operator. The newer feature is that the domain of definition of our Bellman function is infinitely dimensional.

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Fedor Nazarov, Alexander Reznikov, Alexander Volberg. 2014-01-18. Bellman approach to the one-sided bumping for weighted estimates of Calderón--Zygmund operators. https://arxiv.org/abs/1306.2653

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