Principal homogeneous space
= Principal homogeneous space
{wiki=Principal_homogeneous_space}
In mathematics, particularly in the fields of algebra and geometry, a **principal homogeneous space** (or sometimes called a **torsor**) is a structure that captures the idea of "spaces that are acted upon by a group without a distinguished point." Specifically, it is a space that is associated with a group and has the property that the group can act freely and transitively on it.