Homogeneous vacua of (generalized) new massive gravity

Understand

We obtain all homogeneous solutions of new massive gravity models on S^3 and AdS_3 by extending previously known results for the cosmological topologically massive theory of gravity in three dimensions.

• In all cases, apart from the maximally symmetric vacua, there are axially symmetric (i.e., bi-axially squashed) as well as totally anisotropic (i.e., tri-axially squashed) metrics of special algebraic type.
• Transitions among the vacua are modeled by instanton solutions of 3+1 Horava-Lifshitz gravity with anisotropic scaling parameter z=4.