Testing Einstein's objection of 1927 to quantum mechanics opens the door to purely quantum communication

TL;DR

This paper experimentally demonstrates a form of nonlocality in macroscopic electron wavefunctions, supporting standard quantum mechanics over de Broglie's theory and suggesting new avenues for realistic interpretations of quantum phenomena.

Contribution

It provides the first empirical evidence of nonlocality in macroscopic electron wavefunctions, challenging de Broglie's quantum theory and supporting the standard quantum mechanics framework.

Findings

Observation of nonlocality in macroscopic electron wavefunctions

Evidence supporting standard quantum mechanics over de Broglie's theory

Implications for realistic interpretations of quantum formalism

Abstract

Single electron may have wavefunction of a macroscopic lengthscale but cannot be detected in two places. At the Solvay Conference of 1927, Einstein argued that in a combination with Bohr's postulate about wavefunction as an exhaustive characteristics of electron, this fact implies nonlocality related to the collapse of a macroscopic wavefunction of single electron. This was his objection to Bohr's quantum mechanics (QM) in favor of de Broglie's quantum theory. We perform an experimental test in low-temperature state of matter where electrons have macroscopic orbit-like wavefunctions and surprisingly observe nonlocality of that type. This nonlocality differs in principle from the well-known Einstein-Podolsky-Rosen (EPR) nonlocality because the former does not imply quantum entanglement and hence is beyond the no-communication theorem. Our observation is the first empirical justification of the choice in favor of QM in compare with de Broglie's theory. Moreover, now we can expand the current concept of reality and thus open the door to a realistic interpretation of quantum formalism. Ultimately, we thus come to a quantum model of Universe based on the standard QM.