simply connected space
topological space which has no holes through it
spin group
mathematical group which is the double cover of the special orthogonal group SO(n)
Carnot group
simply connected nilpotent Lie group equipped with a derivation of its Lie algebra such that the subspace with eigenvalue 1 generates the Lie algebra
special unitary group
group of unitary matrices with determinant of 1
long line
locally Euclidean topological space that is not paracompact