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arXiv · 1901.04823

On the maximal operator of a general Ornstein-Uhlenbeck semigroup

Valentina Casarino·Paolo Ciatti·Peter Sjögren
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Abstract

If $Q$ is a real, symmetric and positive definite $n\times n$ matrix, and $B$ a real $n\times n$ matrix whose eigenvalues have negative real parts, we consider the Ornstein--Uhlenbeck semigroup on $\mathbb{R}^n$ with covariance $Q$ and drift matrix $B$. Our main result says that the associated maximal operator is of weak type $(1,1)$ with respect to the invariant measure. The proof has a geometric gist and hinges on the "forbidden zones method" previously introduced by the third author.

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Valentina Casarino, Paolo Ciatti, Peter Sjögren. 2019-01-15. On the maximal operator of a general Ornstein-Uhlenbeck semigroup. https://arxiv.org/abs/1901.04823

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