On the Hamiltonian form of 3D massive gravity

Olaf Hohm, Alasdair Routh, Paul K. Townsend, Baocheng Zhang
2012 Physical Review D  
We present a "Chern-Simons-like" action for the "general massive gravity" model propagating two spin-2 modes with independent masses in three spacetime dimensions (3D), and we use it to find a simple Hamiltonian form of this model. The number of local degrees of freedom, determined by the dimension of the physical phase space, agrees with a linearized analysis except in some limits, in particular that yielding "new topologically massive gravity", which therefore suffers from a linearization instability.
doi:10.1103/physrevd.86.084035 fatcat:fqckacbjxfg3fk4eswdpjszgcy