# slow-roll at nth order

19 Feb 2019In inflationary theory, the two slow roll-parameters \(\epsilon\) and \(\eta\) are dimensionless measures of the first and second derivative of the self-interaction \(V(\varphi)\) of the scalar field \(\varphi\): would it make sense to define higher-order slow roll-parameters from the \(n\)th derivative of the potential?