Collapse-Model Force Noise in Gravitational-Wave Interferometers: Computed Spectral Density Against Detector Noise

This paper estimates, under an explicitly stated normalisation, the displacement noise that collapse-model force fluctuations would produce in a gravitational-wave interferometer and compares it with representative detector sensitivity. The displacement amplitude spectral density is 6.333e-29 metres per root hertz at the conventional collapse rate and 6.333e-25 metres per root hertz at a rate of 1e-08 per second, against a representative detector level of 1.00e-19 metres per root hertz near one hundred hertz. On this normalisation the conventional rate lies below detector noise and the stronger rate lies above it, which is why interferometer data already inform the upper part of the parameter range. The normalisation is the main uncertainty and is stated openly. The study is simulated and computed from stated assumptions; it is not a measurement.