243 citations · 3k across the 96 of their papers we have counts for
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Cosmological Gravitational Wave in a Gravity with Quadratic Order Curvature Couplings
H. Noh, J. Hwang
We present a set of equations describing the cosmological gravitational wave in a gravity theory with quadratic order gravitational coupling terms which naturally arise in quantum…
Roles of a coherent scalar field on the evolution of cosmic structures
J. Hwang
A coherently oscillating scalar field, an axion as an example, is known to behave as a cold dark matter. The arguments were usually made in the Newtonian context. Ratra proved the…
Cosmological Perturbations with Multiple Scalar Fields
J. Hwang
In this brief note we present a set of equations describing the evolution of perturbed scalar fields in a cosmological spacetime with multiple scalar fields. We take into account o…
Cosmological Structure Problem of the Pre-Big Bang Scenario
J. Hwang
We calculate the density and gravitational wave spectrums generated in a version of string cosmology termed pre-big bang scenario. The large scale structures are originated from qu…
Quantum fluctuations of Cosmological Perturbations in Generalized Gravity
J. Hwang
Recently, we presented a unified way of analysing classical cosmological perturbation in generalized gravity theories. In this paper, we derive the perturbation spectrums generated…
Evolution of Structures in Generalized Gravity Theories
J. Hwang
A broad class of generalized Einstein's gravity can be cast into Einstein's gravity with a minimally coupled scalar field using suitable conformal rescaling of the metric. Using th…