243 citations · 3k across the 96 of their papers we have counts for
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Newtonian limit of fully nonlinear cosmological perturbations in Einstein's gravity
Jai-chan Hwang, Hyerim Noh
We prove that in the infinite speed-of-light limit (i.e., non-relativistic and subhorizon limits), the relativistic fully nonlinear cosmological perturbation equations in two gauge…
Axion as a cold dark matter candidate: low-mass case
Chan-Gyung Park, Jai-chan Hwang, Hyerim Noh
Axion as a coherently oscillating scalar field is known to behave as a cold dark matter in all cosmologically relevant scales. For conventional axion mass with 10^{-5} eV, the axio…
Fully nonlinear and exact perturbations of the Friedmann world model
Jai-chan Hwang, Hyerim Noh
In 1988 Bardeen has suggested a pragmatic formulation of cosmological perturbation theory which is powerful in practice to employ various fundamental gauge conditions easily depend…
Modern Cosmology: Assumptions and Limits
Jai-chan Hwang
Physical cosmology tries to understand the Universe at large with its origin and evolution. Observational and experimental situations in cosmology do not allow us to proceed purely…
Cosmological post-Newtonian approximation compared with perturbation theory
Hyerim Noh, Jai-chan Hwang
We compare the cosmological first-order post-Newtonian (1PN) approximation with the relativistic cosmological linear perturbation theory in a zero-pressure medium with the cosmolog…
Second order solutions of cosmological perturbation in the matter dominated era
Jai-chan Hwang, Hyerim Noh, Jinn-Ouk Gong
We present the growing mode solutions of cosmological perturbations to the second order in the matter dominated era. We also present several gauge-invariant combinations of perturb…