Frustrated spin model as a hard-sphere liquid
  We show that one-dimensional topological objects (kinks) are natural degrees of freedom for an antiferromagnetic Ising model on a triangular lattice. Its ground states and the coexistence of spin ordering with an extensive zero-temperature entropy can be easily understood in terms of kinks forming a hard-sphere liquid. Using this picture we explain effects of quantum spin dynamics on that frustrated model, which we also study numerically. 
Maxim Mostovoy, Nikolai Prokof'ev, Daniel Khomskii and Jasper Knoester