Perturbations in Regularized Lovelock Gravity

In this paper we study the perturbation theory of recently proposed Regularized Lovelock Gravity (Glavan and Lin, 2020), on curved Friedmann–Lemaître–Robertson–Walker (FLRW) space–time. We provide first order equations both in scalar tensor sector presence an additional minimally coupled field. A general expression for velocity gravitational waves at generic is inferred. Moreover, apply results slow-roll inflation flat FLRW background, second Gravity, i.e. Gauss–Bonnet correction only. derive power spectra perturbations, observable quantities: spectral indices tensor-to-scalar ratio.