Reduced Planck mass (source code)

= Reduced Planck mass
{title2=$M_{\rm Pl}$}

The reduced Planck mass is
$$
M_{\rm Pl}=\sqrt{\frac{\hbar c}{8\pi G}}.
$$
In natural units, Einstein's gravitational coupling is $M_{\rm Pl}^{-2}=8\pi G$.