Luzin N property

The Luzin \( N \) property is a concept from real analysis and functional analysis, particularly in the context of measurable functions. A function \( f: \mathbb{R} \to \mathbb{R} \) is said to have the Luzin \( N \) property if for every measurable set \( E \) of finite measure, the image \( f(E) \) is also a measurable set of finite measure.