A homoclinic tangle, or tendril, is a network of curves leading to a dense area of homoclinic points. In the figures above, let be the point of intersection, with
ahead of
on one manifold and
ahead of
of the other. The mapping of each of these points
and
must be ahead of the mapping of
,
. The only way this can happen is if the manifold
loops back and crosses itself at a new homoclinic point. Another loop must be formed,
with
another homoclinic point. Since
is closer to the hyperbolic point than
, the distance between
and
is less than that between
and
. Area preservation requires the area
to remain the same, so each new curve (which is closer than the previous one) must
extend further. In effect, the loops become longer and thinner. Homoclinic points
appear where chaotic regions touch in a hyperbolic fixed
point.
The homoclinic tangle is the same topological structure as the Smale horseshoe map.