A metric sphere not a quasisphere but for which every weak tangent is Euclidean

Angela Wu

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arXiv · 1806.02917

A metric sphere not a quasisphere but for which every weak tangent is Euclidean

Angela Wu

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Abstract

We show that for all $n \geq 2$, there exists a doubling linearly locally contractible metric space $X$ that is topologically a $n$-sphere such that every weak tangent is isometric to $\R^n$ but $X$ is not quasisymmetrically equivalent to the standard $n$-sphere. The same example shows that $2$-Ahlfors regularity in Theorem 1.1 of \cite{BK02} on quasisymmetric uniformization of metric $2$-spheres is optimal.

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Angela Wu. 2018-06-07. A metric sphere not a quasisphere but for which every weak tangent is Euclidean. https://arxiv.org/abs/1806.02917

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