9 papers
Ultra slow-turn inflation
Ana Achúcarro, Perseas Christodoulidis, Jinn-Ouk Gong +1
In standard multi-field models, tachyonic isocurvature perturbations generally indicate the presence of an instability. We revisit the stability of some known counterexamples and s…
Reheating as a variational probe of cosmological observables
Jinn-Ouk Gong
We formulate reheating as a constrained variational problem in the space of equation-of-state histories, rather than attempting to describe it through microscopic models. We introd…
Kinetic Isocurvature Perturbation
Kyu Jung Bae, Dhong Yeon Cheong, Jinn-Ouk Gong +2
We formulate a new class of primordial perturbations called , where the mass density of dark matter is constant relative to the photon…
Weakly model-independent determination of total expansion during inflation
Dayeong Choi, Subin Jeon, Jinn-Ouk Gong
We study systematically the total expansion experienced by a certain perturbation mode during single-field inflation, not resorting to explicit models of inflation or reheating. By…
Gravitational open effective field theory of inflation
Perseas Christodoulidis, Jinn-Ouk Gong
We construct a gravitational open extension of the effective field theory of inflation in the Schwinger-Keldysh framework. While physical symmetries allow many open operators in th…
Charged Higgs Boson Phenomenology in the Dark Z mediated Fermionic Dark Matter Model
Kyu Jung Bae, Jinn-Ouk Gong, Dong-Won Jung +3
We present the phenomenology of the charged Higgs boson appearing in a fermionic dark matter model mediated by an additional scalar doublet. In order to couple the dark mat…