3 papers
gr-qc2026
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…
hep-th2026
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…
astro-ph.CO2025
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…