857 citations · 4.9k across the 68 of their papers we have counts for
3 papers · 1 filter
Cosmology on all scales: a two-parameter perturbation expansion
Sophia R. Goldberg, Timothy Clifton, Karim A. Malik
We propose and construct a two-parameter perturbative expansion around a Friedmann-Lemaître-Robertson-Walker geometry that can be used to model high-order gravitational effects in…
Linear Density Perturbations in Multifield Coupled Quintessence
Alexander Leithes, Karim A. Malik, David J. Mulryne +1
We study the behaviour of linear perturbations in multifield coupled quintessence models. Using gauge invariant linear cosmological perturbation theory we provide the full set of g…
Double power series method for approximating cosmological perturbations
Andrew J. Wren, Karim A. Malik
We introduce a double power series method for finding approximate analytical solutions for systems of differential equations commonly found in cosmological perturbation theory. The…