Re: Rotations - why are they not vectors


"William Elliot" <marsh@xxxxxxxxxxxxxxxxxx> wrote in message
news:Pine.BSI.4.58.0607152245480.22224@xxxxxxxxxxxxxxxxxxxx
On Sun, 16 Jul 2006, Terry Padden wrote:

Now consider simple (= 1-D) rotations of a spherical object about any
given
fixed axis.

You mean 3D rotations?


NO, you fool. The axis is fixed. Only 1-D rotations are allowed (so far)

Could someone point out to me in what way such 1-D rotations do NOT meet
the
axiomatic criteria for a Vector Space.

In 3D, rotations are represented as a vector in the direction of the axis
of rotation with magnitude of angular displacement.

PLEASE GO AWAY and keep this irrelevant 3-D nonsense to yourself

If 1-D rotations are axiomatically vectors, why cannot they be
axiomatically
compounded into multi-dimensional vector spaces ?

Because the cross product doesn't?


You are showing gross stupidity by this irrelevance. I am asking about
AXIOMS - not mechanics. Please stop embarrassing yourself in public.

NB I am aware that 2-D rotations do-not-commute,

Planar 2D rotations around a point are basically scalars.

That's your own little secret. Keep it that way. Now please go away and
think about axioms for a few years.



.

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