or a more closeup version:

These are pictures in the stress plane w_{1} + w_{2} +w_{3} = 1. Colors of curves correspond to different representations;
Violet here is the 5 dimensional representation while green and red are
3 dimensional. Each curve represents the set of stress triples where
a symmetric tensegrity using that stress and representation is in
equilibrium. The sides of the black triangle correspond to stresses with at
least one entry 0. The interior of the triangle corresponds to all stresses
positive.

As one crosses the **bottom edge** of the triangle, the strut stress changes from
positive to negative. (Choosing a fixed cable stress ratio confines one
to a ray in this diagram.) In this case, paths moving downward from the
bottom edge appear to generally cross the curve of the 5 dimensional
representation first; i.e. it is the apparent ** winner** here.

We say *apparent* here because this is just a Maple implicit plot
based on a relatively coarse grid. Such pictures are suggestive, but
not guarranteed to be correct. Techniques of symbolic algebraic computation
can be used to rigorously establish features we see visually in such plots.

The example illustrated here is a remarkable one. It is the **only**
A5 symmetric tensegrity (with equal cable stresses) where there is a
clearly winning representation but its dimension is greater than 3.

Last Update: *March 5, 1998*