Measure Zero Sets: Proving \sigma(E) Has Measure Zero

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Kindayr
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Homework Statement


Let [itex]\sigma (E)=\{(x,y):x-y\in E\}[/itex] for any [itex]E\subseteq\mathbb{R}[/itex]. If [itex]E[/itex] has measure zero, then [itex]\sigma (E)[/itex] has measure zero.

The Attempt at a Solution


I'm trying to show that if [itex]\sigma (E)[/itex] is not of measure zero, then there exists a point in [itex]E[/itex] such that [itex]\sigma (\{e\})[/itex] that has positive measure. But i don't know if this actually proves the question.

I have already shown that if [itex]E[/itex] open or a [itex]G_{\delta}[/itex] set, then [itex]\sigma (E)[/itex] is also measurable. Can I use these to solve this?

Any help is appreciated.
 
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