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arXiv · 2406.05824

Quasiconformal mappings and the rank of $\tfrac {dDf}{d|Df|}$ for $f\in BV(\mathbb{R}^n; \mathbb{R}^n)$

Panu Lahti
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Abstract

We define a relaxed version $H_f^{\textrm{fine}}$ of the distortion number $H_f$ that is used to define quasiconformal mappings. Then we show that for a BV function $f\in BV(\mathbb{R}^n;\mathbb{R}^n)$, for $|Df|$-a.e. $x\in\mathbb{R}^n$ it holds that $H_{f^*}^{\textrm{fine}}(x)<\infty$ if and only if $\tfrac{dDf}{d|Df|}(x)$ has full rank.

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Panu Lahti. 2024-06-09. Quasiconformal mappings and the rank of $\tfrac {dDf}{d|Df|}$ for $f\in BV(\mathbb{R}^n; \mathbb{R}^n)$. https://arxiv.org/abs/2406.05824

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