ELI5: Explain Like I'm 5

Hilbert space

A Hilbert space is a type of mathematical space that can be used to study many different kinds of shapes and equations. Think of it like a stretching rubber sheet - it can be warped and bent in many different ways. You can also put different kinds of points on the rubber sheet and study how they fit together. Mathematicians use Hilbert spaces to look at a lot different problems and try to find answers.