Slow-roll approximations in Einstein--Gauss--Bonnet gravity formulated in terms of e-folding numbers

Understand

In the Einstein--Gauss--Bonnet (EGB) gravity models, the slow-roll approximation has been extended by taking into account the first-order slow-roll parameter $\delta_1 =-2\,H^2\,\xi^\prime/U_0$, which is proportional to the first derivative of the Gauss-Bonnet coupling function $\xi$ with respect to the e-folding number.

• These extensions lead to the question of the accuracy of effective potential reconstruction during the generalization of attractors in EGB gravity.
• We have reconstructed models using the extended slow-roll approximations and compared them with the exact expressions and the standard slow-roll approximation.