Re: [math-fun] Really, really stupid question about Lorentz group

The "Lorentz" (sub)group is normally not including translations and the "Poincare" group does include them. In informal speech where it does not terribly matter, one often speaks of "Lorentz invariance" or some such, really meaning Poincare, or really meaning the manifold (GR) version of same, figuring the listener understands what you meant. If you really wanted to be careful & precise, you should actually define it each time you use it. -- Warren D. Smith http://RangeVoting.org <-- add your endorsement (by clicking "endorse" as 1st step)