Interferometric Constraints on Spacelike Coherent Rotational Fluctuations

Area of Science:

• Experimental Physics
• Quantum Sensing
• Gravitational Wave Detection

Background:

• Michelson interferometers are crucial for detecting minute displacements.
• Sensing exotic phenomena requires high sensitivity and broad frequency bands.
• Spacetime's rotational degrees of freedom are theorized in quantum geometry.

Purpose of the Study:

• To precisely measure rotationally induced differential position displacements.
• To achieve quantum-limited sensing of spatially correlated signals.
• To constrain semiclassical models of nonlocally coherent spacetime rotational degrees of freedom.

Main Methods:

• Utilized a pair of colocated 39m long, high-power Michelson interferometers.
• Bent one arm of each interferometer 90° to sense rotations about a specific axis.
• Operated the instrument in a broad frequency band beyond the 3.9-MHz inverse light travel time.

Main Results:

• Achieved quantum-limited sensing of rotationally induced differential position displacements.
• Demonstrated sensitivity to rotation-induced strain (h) surpassing CSD_{δh}10 kHz).
• Exceeded sensitivity thresholds relevant to the Planck time (tP).

Conclusions:

• The measurement provides constraints on semiclassical models of spacetime's rotational degrees of freedom.
• Findings are relevant to theories of holographic quantum geometry.
• The experiment advances the capability to probe potential deviations from classical metric theories.