On Apr 5, 2011, at 11:55 PM, Richard Briet wrote:

Chris:

I just commented on your other email.

I think we do not have to go to higher dimensional spaces as you suggested.

Curved space, like for example on the surface of a sphere, will do the trick.

If I may quote you:

If we could find a case where three different forces cancelled out without being in the same plane or on the same line through the origin, we'd have proof that we had a four-dimensional space at that point.

Therefore, instead of saying "we'd have proof that we had a four-dimensional space at that point." I would have said "we'd have proof that space is curved at that point."

Do you agree?

Richard.