Nonlocality beyond quantum mechanics

Andrey Anatoljevich Grib, Waldyr A. Rodrigues

Zeng‐Bing Chen, Sixia Yu, Zhang, Yong-De +1 more

Although entanglement is widely recognized as one of the most fascinating characteristics of quantum mechanics, nonlocality remains to be a big labyrinth. The proof of existence of nonlocality is as yet not much convincing because of its strong reliance on Bell's theorem where the assumption of realism weakens the proof. We demonstrate that entanglement and quantum nonlocality are two equivalent aspects of the same quantum wholeness for spacelike separated quantum systems. This result implies that quantum mechanics is indeed a nonlocal theory and lays foundation of understanding quantum nonlocality beyond Bell's theorem.

Abner Shimony

Sandu Popescu, Daniel Rohrlich

Quantum mechanics permits nonlocality---both nonlocal correlations and nonlocal equations of motion---while respecting relativistic causality. Is quantum mechanics the unique theory that reconciles nonlocality and causality? We consider two models, going beyond quantum mechanics, of nonlocality---``superquantum" correlations, and nonlocal ``jamming" of correlations---and derive new results for the jamming model. In one space dimension, jamming allows reversal of the sequence of cause and effect; in higher dimensions, however, effect never precedes cause.

S. A. Emelyanov

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.

Thomas A. Brody, L. de la Peña-Auerbach