Superposition Trap: An experimental concept to quantify the quantum collapse rate

The Measurement Problem has remained at the pinnacle of unresolved mysteries ever since the dawn of quantum theory. There are myriads of theories that give possible resolutions to the problem. There is a class of theories which modify the Schrodinger equation to give provisions for the collapse of the wave-function. Such models provide a rate of collapse which depends on different characteristics of the object in superposition. In order to test such models one is required to have means to quantify the rate of collapse of superposition.

 

Directly coupling a measurement device to the system under study is not an ideal way to quantify the collapse rate, as this coupling itself leads to collapse. Thus, we propose a novel experimental concept which can provide a better quantification of the rate of collapse. The core idea involves containing the quantum object as long as it remains in the superposition—it only escapes the system if the superposition collapses. One can achieve such an effect by utilizing the phenomenon of interference, by constructing trapping geometries such that at the points of escape there is destructive interference. In such a case the destructive interference is only lifted if the wave-function undergoes a collapse.  Henceforth, the effective wave-function will give an extra finite probability density outside the trap . This probability density can then be detected by a detector placed outside the trap. In an ideal case the detector will not be able to couple with the superposition. Thus it cannot initiate a collapse. Hence, one will have better control over the parameters contributing to the collapse. We dub such a trap as a “superposition trap.” Such an apparatus, if realized, will help in advancing our understanding of quantum collapses. We propose a particular implementation of the trap using an atom interferometer.