99 citations · 558 across the 40 of their papers we have counts for
40 papers
Curvature and Isocurvature Perturbations in multi-field Gauss-Bonnet inflation
Seoktae Koh
We study cosmological perturbations in multi-field inflation in which the scalar fields couple to the Gauss-Bonnet terms through a general coupling function . We derive the…
Ermakov-Lewis invariant in single field inflation
Seoktae Koh
We investigate the dynamical symmetry of the Sasaki-Mukhanov equation, which governs the evolution of primordial perturbations during inflation. By mapping the Sasaki-Mukhanov equa…
Implications of pulsar timing arrays for Gauss-Bonnet Inflation
Reginald Christian Bernardo, Seoktae Koh, Gansukh Tumurtushaa
Correlated time-of-arrival measurements by pulsar timing arrays (PTAs) have provided a new means of constraining astrophysical or cosmological models that produce a gravitational w…
Higgs Inflation with a Gauss-Bonnet term
Seoktae Koh, Seong Chan Park, Gansukh Tumurtushaa
Higgs inflation with a Gauss-Bonnet term is studied in the Einstein frame. Our model features two coupling functions, and , coupled to the Ricci scalar and Gauss-Bon…
Existence of gradient CKV and gradient conformally stationary LRS spacetimes
Seoktae Koh, Abbas M Sherif, Gansukh Tumurtushaa
In this work, we study the existence of gradient (proper) CKVs in locally rotationally symmetric spacetimes (LRS), those CKVs in the space spanned by the tangent to observers' cong…
Dynamical Compactification with Matter
Kyung Kiu Kim, Seoktae Koh, Gansukh Tumurtushaa
In this work, we study cosmological solutions of the 8-dimensional Einstein Yang-Mills theory coupled to a perfect-fluid matter. A Yang-Mills instanton of extra dimensions causes a…