I consider a thought experiment measuring the decoherence for quasiclassical superpositions of gravitational field. A version of the hole argument allows to prove that a covariant (background-free) theory is completely unable to define the outcome of this experiment and is therefore not viable. Instead, the results of experiments of this type allow to reconstruct a common background shared by all superposed gravitational fields.
Quantum coherent dynamics of quasiclassical spacetimes
University of Waterloo（滑铁卢大学）；Waterloo Centre for Astrophysics, University of Waterloo（滑铁卢大学天体物理中心）；The University of Queensland（昆士兰大学）；Centre for Quantum Computation and Communication Technology, School of Mathematics and Physics, The University of Queensland（昆士兰大学数学与物理学院量子计算与通信技术研究中心）；Pusan National University（釜山国立大学）；Department of Physics Education, Pusan National University（釜山国立大学物理教育系）；Research Center for Dielectric and Advanced Matter Physics, Pusan National University（釜山国立大学介电与先进物质物理研究中心）；National Taiwan University（台湾大学）；Leung Center for Cosmology and Particle Astrophysics, National Taiwan University（台湾大学梁林宇宙学与粒子天体物理中心）；Perimeter Institute for Theoretical Physics（理论物理珀尔默特研究所）；Institute for Quantum Computing, University of Waterloo（滑铁卢大学量子计算研究所）
The Einstein-Podolsky-Rosen (EPR) paradox is one of the milestones in quantum foundations, arising from the lack of local realistic description of quantum mechanics. The EPR paradox has stimulated an important concept of "quantum nonlocality", which manifests itself by three different types: quantum entanglement, quantum steering, and Bell nonlocality. Although Bell nonlocality is more often used to show the "quantum nonlocality", the original EPR paradox is essentially a steering paradox. In this work, we formulate the original EPR steering paradox into a contradiction equality,thus making it…
Correlations between distant particles are central to many puzzles and paradoxes of quantum mechanics and, at the same time, underpin various applications like quantum cryptography and metrology. Originally in 1935, Einstein, Podolsky and Rosen (EPR) used these correlations to argue against the completeness of quantum mechanics. To formalise their argument, Schrödinger subsequently introduced the notion of quantum steering. Still, the question which quantum states can be used for the EPR argument and which not remained open. Here we show that quantum steering can be viewed as an inclusion prob…
On the seminal paper written by Einstein, Podolsky and Rosen [1], a critique to the completeness of quantum mechanics was posed. Part of the critique consisted in the following argument: if quantum mechanics is complete, then, two physical quantities, with non-commuting operators, can have simultaneous reality. In this paper I aim to provide a pedagogical approach to the notions used in the EPR's argument.
A critical reconsideration of the EPR (Einstein-Podolsky-Rosen) paper shows that the EPR argument can be developed without using the concept of `element of physical reality', thus eliminating any philosophical element in the logical chains of the paper. Deprived of its philosophical ornament, the EPR argument plainly reduces to require what quantum mechanics can not do: to assign definite values to two incompatible physical quantities. Hidden variables theories built up according to Bell - type theorems are formulated on the basis of the assumption that the locality condition implies the stati…
