Path: utzoo!attcan!uunet!mailrus!husc6!m2c!wpi!fenn
From: fenn@wpi.wpi.edu (Brian Fennell)
Newsgroups: comp.graphics
Subject: Re: 4-Space Basis Rotation Matrices
Message-ID: <14503@wpi.wpi.edu>
Date: 14 Aug 90 13:58:10 GMT
References: <2498@ryn.esg.dec.com> <1538@seti.inria.fr> <140587@sun.Eng.Sun.COM>
Reply-To: fenn@wpi.wpi.edu (Brian Fennell)
Organization: Worcester Polytechnic Institute, Worcester ,MA
Lines: 23

In article <140587@sun.Eng.Sun.COM> falk@peregrine.Sun.COM (Ed Falk) writes:
...
>I think a simpler way to think of it is this:  the idea that rotations
>are around an *axis* is incorrect.  It just happens to work in
>three dimensions.  In fact, rotations occur within a *plane*.  In
>4D, there are six planes (XY, XZ, XW, YZ, YW, ZW) and the rotations
>through those various planes are
...
>	-ed falk, sun microsystems -- sun!falk, falk@sun.com
....

Granted that the idea of rotation in 4D seems to best apply to manipulating
points in (or around) a plane, but that brings up the question: are
there any 4D manipulations that are not the aforementioned
rotation, and still maintain the integrity of the object?  By
maintaining integrity" I mean that any given point A maintains its
distance from any other 5 non-co-spatial (not in the same 3-space) points 
B, C, D, E, and F.  

Hmmm, this seems to be getting out of the "graphics" arena.  What other
news groups would tailored to this discussion?

Brian Fennell == fenn@wpi.wpi.edu