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arXiv · 1708.02304

Rectifiability of measures and the $\beta_p$ coefficients

Xavier Tolsa
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Abstract

In some former works of Azzam and Tolsa it was shown that $n$-rectifiability can be characterized in terms of a square function involving the David-Semmes $\beta_2$ coefficients. In the present paper we construct some counterexamples which show that a similar characterization does not hold for the $\beta_p$ coefficients with $p\neq2$. This is in strong contrast with what happens in the case of uniform $n$-rectifiability. In the second part of this paper we provide an alternative argument for a recent result of Edelen, Naber and Valtorta about the $n$-rectifiability of measures with bounded lower $n$-dimensional density. Our alternative proof follows from a slight variant of the corona decomposition in one of the aforementioned works of Azzam and Tolsa and a suitable approximation argument.

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Xavier Tolsa. 2017-08-07. Rectifiability of measures and the $\beta_p$ coefficients. https://arxiv.org/abs/1708.02304

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