In
geometry, a
half-space is either of the two parts into which a
plane divides the three-dimensional
Euclidean space. More generally, a
half-space is either of the two parts into which a
hyperplane divides an
affine space. That is, the points that are not incident to the hyperplane are
partitioned into two
convex sets (i.e., half-spaces), such that any subspace connecting a point in one set to a point in the other must intersect the hyperplane.