# Plane (physics)

In

physics, a

**plane** is

surface which is

*plane*; i.e. the

volume of any

3-simplex of four distinct elements of this

*plane* is zero, as evaluated from the

distances measured (pairwise) between these elements, by

Tartaglia's formula.

The elements of such a plane (and the distance relations between them) can also be represented mathematically, namely as a *2-manifold*.