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For $E \subset \mathbb{R}^n$ put $\Delta(E) = \lbrace |x - y| : x,y \in E \rbrace$, where $| \cdot |$ denotes Euclidean distance. Then for finite sets $E \subset \mathbb{R}^2$, there exists a universal constant such that
$$|\Delta(E)| \geq c \frac{|E|}{\log |E|}.$$