Skip to main content
2 of 7
deleted 438 characters in body
Piotr Hajlasz
  • 28k
  • 5
  • 86
  • 186

The answer is yes. There is a strictly increasing function $f:\mathbb{R}\to\mathbb{R}$ such that $f'(x)=0$ for a.e. $x$. This function maps a set of full measure to a set of measure zero and a set of measure zero to a set of full measure. I will try to find some references.

Piotr Hajlasz
  • 28k
  • 5
  • 86
  • 186