Translation of a set

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Let $A\subset \mathbb R$ be Lebesgue measurable set. Is it true that if $\ \forall r\in(0,1)$ $$A\cap (A+r)\neq \emptyset$$ then $\lambda(A)>0$? $$$$ I think that is linked to the Vitali set, but I did't manage to prove it.

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No.

Take for instance the Cantor set on $[0,1]$

We have that $m(C)=0$ and $C-C=[-1,1]$

Thus $(0,1) \subseteq C-C\Longrightarrow C \cap(C+r) \neq \emptyset,\forall r \in (0,1)$