Modulated Accelerating Mirrors as a Physical Realization of the Kappa-Gamma Vacuum

Modulated accelerating mirrors provide a concrete dynamical origin for the $\kappa\gamma$ vacuum-a thermal, single-mode squeezed state with a tunable angle. The Carlitz-Willey trajectory fixes the Planckian weights (set by $\kappa$), while a weak, chiral, frequency-diagonal boundary drive-equivalently a time-dependent Robin impedance-rotates the squeeze angle (set by $\gamma$) without changing those weights at leading order. On future null infinity, the two-point function cleanly splits into a stationary thermal piece and a phase-sensitive, non-stationary piece. Inertial Unruh-DeWitt detectors see an exact Planck law; uniformly accelerated detectors expose $\gamma$ through interference and can show mode-selective suppression under frequency matching. Numerical wave-packet simulations corroborate the phase imprint and parametric amplification. In short: trajectory sets scale, boundary sets angle. This separation turns abstract squeeze parameters into laboratory-tunable signatures and offers a practical route to engineer and diagnose $\kappa\gamma$ vacua in moving-mirror analogs.