%0 Journal Article %T Fluctuating semiflexible polymer ribbon constrained to a ring %A Karen Alim %A Erwin Frey %J Quantitative Biology %D 2007 %I arXiv %R 10.1140/epje/i2007-10228-x %X Twist stiffness and an asymmetric bending stiffness of a polymer or a polymer bundle is captured by the elastic ribbon model. We investigate the effects a ring geometry induces to a thermally fluctuating ribbon, finding bend-bend coupling in addition to twist-bend coupling. Furthermore, due to the geometric constraint the polymer's effective bending stiffness increases. A new parameter for experimental investigations of polymer bundles is proposed: the mean square diameter of a ribbonlike ring, which is determined analytically in the semiflexible limit. Monte Carlo simulations are performed which affirm the model's prediction up to high flexibility. %U http://arxiv.org/abs/0708.0111v2