The DNA Mini-Circle Problem
On short length scales the DNA double `helix' is quite
stiff and has a minimum energy, open, intrinsic shape (left figure). The
ends of the `helix' are sticky and molecules sometimes catch their own
tails to cyclize (centre). The molecule can cyclize with different links
of the double helices. We model the DNA as an elastic rod and capture all
possible links, by a continuation computation in the imposed angle alpha
(right).