First Hubble slow-roll parameter
= First Hubble slow-roll parameter
{title2=$\epsilon$}
The first Hubble slow-roll parameter is
$$
\epsilon=-\frac{\dot H}{H^2}.
$$
For a canonical inflaton, $\epsilon=\dot\phi^2/(2M_{\rm Pl}^2H^2)\geq0$.
= First Hubble slow-roll parameter
{title2=$\epsilon$}
The first Hubble slow-roll parameter is
$$
\epsilon=-\frac{\dot H}{H^2}.
$$
For a canonical inflaton, $\epsilon=\dot\phi^2/(2M_{\rm Pl}^2H^2)\geq0$.