An exotic theory of massless spin-2 fields in three dimensions

It is a general belief that the only possible way to consistently deform th e Pauli-Fierz action, also changing the gauge algebra, is general relativit y. Here we show that a different type of deformation exists in three dimens ions if one allows for PT non-invariant terms. The new gauge algebra is dif ferent from that of diffeomorphisms. Furthermore, this deformation can be g eneralized to the case of a collection of massless spin-2 fields. In this c ase it describes a consistent interaction among them.