Article published in Phys. Rev. Research (Rapid Communication)
Our article Many-particle interference to test Born’s rule has been published as a Rapid Communication in Phys. Rev. Research:
Phys. Rev. Research 2, 012051(R) (2020)
Abstract:
Born’s rule relates detection probabilities to the modulus square of the wave function. It is one of the central principles of quantum mechanics together with that of linear superposition. Single-particle interference is accordingly limited to pairs of quantum paths and higher-order interferences are prohibited. Deviations from Born’s law have been quantified via the Sorkin parameter which is proportional to the third-order term. However, while the linearity of quantum theory has been experimentally tested to the level of 10-20 eV, the Sorkin parameter has only been measured to an accuracy of 2x10-3 in the quantum regime. We here investigate Born’s law using many-particle interferences and demonstrate that all interference terms of order (2M+1) and greater vanish for M particles. We further introduce a family of many-particle Sorkin parameters and show that they are exponentially more sensitive to deviations from Born’s rule than their single-particle counterpart.