Whether it’s to meet for dinner, attend a lecture, or play baseball, one of the first questions is *“where?”* Everything that takes place, takes place some *place* (and some *time*, but that’s another question).

Where quantum mechanics takes place is a challenging ontological issue, but the way we compute it is another matter. The *math* takes place in a *complex vector space* known as

**Hilbert space**(“complex” here refers to the complex numbers, although the traditional sense does also apply a little bit).

Mathematically, a *quantum state* is a ** vector** in Hilbert space.