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arXiv · 1910.00364

Iterated commutators under a joint condition on the tuple of multiplying functions

Tuomas Hytönen·Kangwei Li·Tuomas Oikari
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Abstract

We present a pair of joint conditions on the two functions $b_1,b_2$ strictly weaker than $b_1,b_2\in \operatorname{BMO}$ that almost characterize the $L^2$ boundedness of the iterated commutator $[b_2,[b_1,T]]$ of these functions and a Calder\'on-Zygmund operator $T.$ Namely, we sandwich this boundedness between two bisublinear mean oscillation conditions of which one is a slightly bumped up version of the other.

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Tuomas Hytönen, Kangwei Li, Tuomas Oikari. 2019-10-01. Iterated commutators under a joint condition on the tuple of multiplying functions. https://doi.org/10.1090/proc/15101

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