The Nambu-Goto action is an action functional for sigma-models with target space a (pseudo) Riemannian manifold : it is the induced volume functional
where is the volume form of the pullback of the metric tensor from to .
This is classically equivalent (…) to the Polyakov action.
The NG-action serves as the kinetic action functional of the sigma-model that described a fundamental brane propagating on . For this is the relativistic particle, for the string, for the membrane.
One string theory textbook that deals with the Nambu-Goto action in a bit more detail than usual is
Revised on May 31, 2011 17:49:10
by Urs Schreiber