27 Jan
2008
27 Jan
'08
9:42 p.m.
On 1/28/08, Fred lunnon <fred.lunnon@gmail.com> wrote:
.... Indeed, this approach appears to work perfectly satisfactorily provided only proper isometries are involved [or incidentally if k = n]: the traditional representation of a flats by quotients of (Pluecker) coordinate vectors over nonnegative reals has to be replaced by quotients over positive reals; then a change of sign indicates a change of orientation. ...
Duh! For "nonnegative" read "nonzero". WFL