Counterrotational effects on stability of 2+1-dimensional thin-shell   wormholes
  The role of angular momentum in a 2+1-dimensional rotating thin-shell wormhole (TSW) is considered. Particular emphasis is made on stability when the shells (rings) are counterrotating. We find that counter-rotating halves make the TSW supported by the equation of state of a linear gas more stable. Under a small velocity dependent perturbation, however, it becomes unstable. 
S. Habib Mazharimousavi and M. Halilsoy
gr-qc