On arithmetic sums of connected sets in $\mathbb{R}^2$

Yu-Feng Wu

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arXiv · 2207.03778

On arithmetic sums of connected sets in $\mathbb{R}^2$

Yu-Feng Wu

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Abstract

We prove that for two connected sets $E,F\subset\mathbb{R}^2$ with cardinalities greater than $1$, if one of $E$ and $F$ is compact and not a line segment, then the arithmetic sum $E+F$ has non-empty interior. This improves a recent result of Banakh, Jab{\l}o\'nska and Jab{\l}o\'nski [4,Theorem 4] in dimension two by relaxing their assumption that $E$ and $F$ are both compact.

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Yu-Feng Wu. 2022-07-08. On arithmetic sums of connected sets in $\mathbb{R}^2$. https://arxiv.org/abs/2207.03778

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