Jiggled interferometer: Ground-based gravitational wave detector using rapidly-repeated free-falling test masses

We propose the Jiggled Interferometer (JIGI), a novel ground-based gravitational wave detector with space-like sensitivity. Using rapidly-repeated free-fall test masses, JIGI eliminates seismic and suspension thermal noise during free fall. Compared to the Juggled Interferometer, it offers improved angular stability and avoids tracking lasers. We analyze detrending--a required step to remove actuation-induced noise--and show sensitivity gains of about four orders of magnitude in the 0.1-0.3 Hz band, relative to seismic and suspension noise extrapolated from the Cosmic Explorer.