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arXiv · 1406.5743

On a theorem of M. Cartwright in higher dimensions

A. Logunov·E. Malinnikova·P. Mozolyako
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Abstract

We consider harmonic functions in the unit ball of $\mathbb{R}^{n+1}$ that are unbounded near the boundary but can be estimated from above by some (rapidly increasing) radial weight $w$. Our main result gives some conditions on $w$ that guarantee the estimate from below on the harmonic function by a multiple of this weight. In dimension two this reverse estimate was first obtained by M. Cartwright for the case of the power weights, $w_p(z)=(1-|z|)^{-p}$ for $p>1$, and then generalized to a wide class of regular weights by a number of authors.

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A. Logunov, E. Malinnikova, P. Mozolyako. 2014-06-22. On a theorem of M. Cartwright in higher dimensions. https://doi.org/10.1112/jlms%2Fjdv060

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