Tradeoff between extractable mechanical work, accessible entanglement,   and ability to act as a reference system, under arbitrary superselection   rules
  Superselection rules (SSRs) limit the mechanical and quantum processing resources represented by quantum states. However SSRs can be violated using reference systems to break the underlying symmetry. We show that there is a duality between the ability of a system to do mechanical work and to act as a reference system. Further, for a bipartite system in a globally symmetric pure state, we find a triality between the system's ability to do local mechanical work, its ability to do ``logical work'' due to its accessible entanglement, and its ability to act as a shared reference system. 
J.A. Vaccaro, F. Anselmi, H. M. Wiseman and K. Jacobs