# Propagating degrees of freedom of graviton

What is the best way to see that the number of propagating degrees of freedom or gravitons in 3 dimensions is $0$ ? By graviton I mean the metric and NOT some topologically massive graviton that one can include in the Lagrangian. Also is the number in 4-dimensions 2?

• This question (v3) is also addressed in e.g this and this Phys.SE answers. – Qmechanic Jan 31 '13 at 13:04