= String-frame metric
{title2=$g^{(s)}_{ab}$}
= String frame
{synonym}
The string-frame metric is the target metric appearing directly in the kinetic term of the <string nonlinear sigma model>. With conventional Euclidean <dilaton> $\varphi$, its leading spacetime gravitational action contains $\sqrt{-g^{(s)}}e^{-2\varphi}(R+4|\nabla\varphi|^2)$. The dilaton-dependent Ricci coefficient distinguishes it from the <Einstein-frame metric>. Frame changes are local field redefinitions where the conformal factor is finite and nonzero; the <Lorentzian dilaton coupling sign convention> fixes which named field is $\varphi$.
Back to article page
