Does quantum vacuum noise doom ultra-sensitive dark matter detectors?

Paired superradiance amplifies faint signals from dark matter or neutrinos by a factor proportional to volume squared—but treating it as a quantum device reveals a hidden constraint. Quantum vacuum fluctuations, not just thermal noise, seed macroscopic photon bursts when the gain exceeds a critical threshold (ΓL=π/2). This sets a previously unknown limit on how large and sensitive these detectors can become.