Working Around the Uncertainty PrincipleCategory: Science & Technology
Posted: May 23, 2014 08:01AM
Among the many consequences of quantum mechanics are the uncertainty principles. Simply put, these mathematical formulae place firm limits on the accuracy with which you can make measurements of quantum objects. While there is no way to avoid these principles, researchers at the California Institute of Technology have found a trick to get around them and make measurements more accurate than normally possible.
If you want to measure where an object is, such as an atom or molecule, you have to bounce something off of it, and see how that something, often photons, behaves. While photons that strike the object do return useful information, photons that do not strike it or reflect off of it at different times will produce noise and error in the measurement. To get around this the Caltech researchers added a mechanical device consisting of two metal plates vibrating with a frequency of 4 MHz. This device was coupled to a superconducting electronic resonator, which vibrated at 5 GHz and was the target of microwaves. The researchers observed that the noisy photons bouncing off of the superconductor also struck the metal plates and actually caused it to shake with an amplitude about the diameter of a proton.
Though the diameter of a proton is almost unimaginably small, the researchers were still able to use this information about the noise to correct the system and reduce its impact on the measurement. Eventually this research could lead to some interesting studies and applications, as it demonstrated a means to link the noise of uncertainty to a macroscopic object. Those metal plates were about the size of a human hair.