4 papers
Real-time Gravitational Wave Response in Thermal Spinning fields
Atsuhisa Ota, Hui-Yu Zhu, Yuhang Zhu
We study how the spin content of the thermal plasmas affects the propagation of gravitational waves in a radiation-dominated universe. As a simple but representative setup, we cons…
Symmetry principles of gravitational perturbations in thermal environments
Atsuhisa Ota
The thermal plasma induces a plasmon-like mass shift for gravitational perturbations, which can modify their dynamics near the horizon scale in the early radiation-dominated univer…
Graviton stimulated emission in squeezed vacuum states
Atsuhisa Ota, Yuhang Zhu
We study the dynamics of gravitons in a squeezed vacuum state under a thermal radiation background. Unlike traditional treatments that rely on the Boltzmann equation, we employ the…
Cosmological stimulated emission
Atsuhisa Ota
We study stimulated emission and absorption of gravitons in a squeezed vacuum state immersed in a thermal radiation bath. Employing one-loop interaction-picture perturbation theory…