Revealing photons' past via quantum twisted double-slit experiment

TL;DR

This paper presents a quantum twisted double-slit experiment that demonstrates photons' wavefunctions represent their real existence and evolution, addressing fundamental questions about the reality of quantum states.

Contribution

It introduces a novel experiment exploiting twisted photons to reveal the true nature of photons during propagation, challenging traditional views on wavefunction collapse.

Findings

Photons' arrival times differ from measurement states but match during propagation

Wavefunctions depict the real existence and evolution of quantum entities

Clarifies the role of wavefunctions beyond mere measurement probabilities

Abstract

Are quantum states real? This most fundamental question in quantum mechanics has not yet been satisfactorily resolved, although its realistic interpretation seems to have been rejected by various delayed-choice experiments. Here, to address this long-standing issue, we present a quantum twisted double-slit experiment. By exploiting the subluminal feature of twisted photons, the real nature of a photon during its time in flight is revealed for the first time. We found that photons' arrival times were inconsistent with the states obtained in measurements but agreed with the states during propagation. Our results demonstrate that wavefunctions describe the realistic existence and evolution of quantum entities rather than a pure mathematical abstraction providing a probability list of measurement outcomes. This finding clarifies the long-held misunderstanding of the role of wavefunctions and their collapse in the evolution of quantum entities.