IQIM Postdoctoral and Graduate Student Seminar

Note: this is a Special IQIM seminar. Tuesday, January 13 beginning at 1 pm in 153 Noyes

Abstract: We propose an Earth-based, laboratory-scale experiment capable of measuring the Earth's generalrelativistic frame-dragging at the 0.2% level in one second using the macroscopic quantum properties of a novel superfluid ⁴He single Josephson junction gyrometer. We derive the frame-dragging and related geodetic and Thomas precession effects in such a gyrometer, emphasizing that all three effects, in addition to the Sagnac effect, can be thought of as frame-dragging effects in a reference frame co-moving with the gyrometer. Using a novel thermal noise analysis for such a superfluid ⁴He gyrometer operating at mK temperatures, we estimate that a thermal noise spectral density of 5×10⁻¹⁷rads/s/√Hz should be achievable. In a one-second measurement, this gives a rotational sensitivity of 1 revolution in 4 Byrs, or 0.2% of the Earth's frame-dragging precession rate. We show that this extreme sensitivity corresponds to a measurement of proper time differences as small as 10⁻³⁵ s.