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Experimental limits for low-frequency space-time fluctuations from ultrastable optical resonators

S. Schiller·C. Laemmerzahl·H. Mueller·C. Braxmaier·S. Herrmann·A. Peters
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Abstract

It has been suggested that space-time might undergo fluctuations because of its intrinsic quantum nature. These fluctuations would pose a fundamental limit to the ability of measuring distances with arbitrary precision, beyond any limitations due to standard quantum mechanics. Laser interferometers have recently been proposed as being suited for a search for the existence of space-time fluctuations. Here we present results of a search for space-time fluctuations of very low fluctuation frequencies, in the range from 1 microHz to 0.5 Hz. Rigid optical interferometers made out of sapphire and operated at cryogenic temperature were used. We find an upper limit of 1.10^-24 Hz^-1 for the normalized distance noise spectral density at 6 microHz, and of 1.10^-28 Hz^-1 above 5 mHz, and establish an experimental limit for the parameter of a recently proposed random-walk hypothesis.

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S. Schiller, C. Laemmerzahl, H. Mueller, C. Braxmaier, S. Herrmann, A. Peters. 2004-01-26. Experimental limits for low-frequency space-time fluctuations from ultrastable optical resonators. https://doi.org/10.1103/physrevd.69.027504

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