Evolution of the curvature perturbation during and after multi-field inflation. (2009)
Choi, Ki-Young, Gong, Jinn-Ouk, Jeong, Donghui
We study the evolution of the curvature perturbation on the super-horizon scales starting from the inflationary epoch until there remains only a single dynamical degree of freedom, presureless...
Towards a warped inflationary brane scanning (2008)
We present a detailed systematics for comparing warped brane inflation with the observations, incorporating the effects of both moduli stabilization and ultraviolet bulk physics. We explicitly...
Evolution of the curvature perturbation during and after multi-field inflation (2008)
Choi, Ki-Young, Gong, Jinn-Ouk, Jeong, Donghui
We study the evolution of the curvature perturbation on the super-horizon scales starting from the inflationary epoch until there remains only a single dynamical degree of freedom, presureless...
Punctuated inflation and the low CMB multipoles (2008)
Jain, Rajeev Kumar, Chingangbam, Pravabati, Gong, Jinn-Ouk, Sriramkumar, L., Souradeep, Tarun
We investigate inflationary scenarios driven by a class of potentials which are similar in form to those that arise in certain minimal supersymmetric extensions of the standard model. We find that...
Systematics of multi-field effects at the end of warped brane inflation (2008)
Chen, Heng-Yu, Gong, Jinn-Ouk, Shiu, Gary
We investigate in the context of brane inflation the possibility of additional light scalar fields generating significant power spectrum and non-Gaussianities at the end of inflation affecting the...
Systematics of multi-field effects at the end of warped brane inflation (2008)
Chen, Heng-Yu, Gong, Jinn-Ouk, Shiu, Gary
We investigate in the context of brane inflation the possibility of additional light scalar fields generating significant power spectrum and non-Gaussianities at the end of inflation affecting the...
Curvature perturbation spectrum from false vacuum inflation (2008)
In the inflationary cosmology it occurs frequently that the inflaton field is trapped in a local, transient minimum with non-zero vacuum energy. The difficulty regarding the curvature perturbation...
Minimal gauge inflation (2008)
Gong, Jinn-Ouk, Park, Seong Chan
We consider a gauge inflation model in the simplest orbifold M4 x S1/Z2 with the minimal non-Abelian SU(2) hidden sector gauge symmetry. The inflaton potential is fully radiatively generated solely...
The lessons from the running of the tensor-to-scalar ratio (2007)
We derive a simple consistency relation from the running of the tensor-to-scalar ratio. This new relation is first order in the slow-roll approximation. While for single field models we can obtain...
Sustainability of multi-field inflation and bound on string scale (2007)
We study the effects of the interaction terms between the inflaton fields on the inflationary dynamics in multi-field models. With power law type potential and interactions, the total number of...
Generation of perturbation after multi-field inflation (2007)
We explore a new possibility that some inflaton fields in multi-field inflation models satisfy the observed value of the spectral index so that the curvature perturbation generated by them through...
Inflation in minimal left-right symmetric model with spontaneous D-parity breaking (2007)
Gong, Jinn-Ouk, Sahu, Narendra
We present a simplest inflationary scenario in the minimal left-right symmetric model with spontaneous D-parity breaking, which is a well motivated particle physics model for neutrino masses. This...
Multiple scalar particle decay and perturbation generation (2007)
Choi, Ki-Young, Gong, Jinn-Ouk
We study the evolution of the universe which contains a multiple number of non-relativistic scalar fields decaying into both radiation and pressureless matter. We present a powerful analytic...
End of multi-field inflation and the perturbation spectrum (2006)
We investigate the dynamics of inflation models driven by multiple, decoupled scalar fields and calculate the Hubble parameter and the amplitude of the lightest field at the end of inflation which...
On two string axions as inflaton (2006)
We study an inflationary model where two decoupled string axions drive inflation. The number of e-folds is dependent on the energy scale and the decay constant, but is almost independent of the...
Modular thermal inflation without slow-roll approximation (2006)
We study an inflationary scenario where thermal inflation is followed by fast-roll inflation. This is a rather generic possibility based on the effective potentials of spontaneous symmetry breaking...
Dark energy in hybrid inflation (2005)
Gong, Jinn-Ouk, Kim, Seongcheol
The situation that a scalar field provides the source of the accelerated expansion of the universe while rolling down its potential is common in both the simple models of the primordial inflation and...
From the Spectrum to Inflation : An Inverse Formula for the General Slow-Roll Spectrum (2005)
Joy, Minu, Stewart, Ewan D., Gong, Jinn-Ouk, Lee, Hyun-Chul
We propose a general inverse formula for extracting inflationary parameters from the observed power spectrum of cosmological perturbations. Under the general slow-roll scheme, which helps to probe...
General Slow-Roll Spectrum for Gravitational Waves (2004)
We derive the power spectrum P_\psi(k) of the gravitational waves produced during general classes of inflation with second order corrections. Using this result, we also derive the spectrum and the...
Second Order General Slow-Roll Power Spectrum (2004)
Choe, Jeongyeol, Gong, Jinn-Ouk, Stewart, Ewan D.
Recent combined results from the Wilkinson Microwave Anisotropy Probe (WMAP) and Sloan Digital Sky Survey (SDSS) provide a remarkable set of data which requires more accurate and general...