Does gravity induce wavefunction collapse? An examination of Penrose's conjecture

Abstract

According to Penrose, the fundamental conflict between the superposition principle of quantum mechanics and the principle of general covariance of general relativity entails the existence of wavefunction collapse, e.g. a quantum superposition of two different space-time geometries will collapse to one of them due to the ill-definedness of the time-translation operator for the superposition. In this paper, we argue that Penrose's conjecture on gravity's role in wavefunction collapse is debatable. First of all, it is still a controversial issue what the exact nature of the conflict is and how to resolve it. Secondly, Penrose's argument by analogy is too weak to establish a necessary connection between wavefunction collapse and the conflict as understood by him. Thirdly, the conflict does not necessarily lead to wavefunction collapse. For the conflict or the problem of ill-definedness for a superposition of different space-time geometries also needs to be solved before the collapse of the superposition finishes, and once the conflict has been resolved, the wavefunction collapse will lose its physical basis relating to the conflict. In addition, we argue that Penrose's suggestions for the collapse time formula and the preferred basis are also problematic.

10 pages, no figures

References in corpus (9)

• Gravitation and quantummechanical localization of macroobjects
• Relativistic state reduction dynamics
• The Schrödinger-Newton equation as non-relativistic limit of self-gravitating Klein-Gordon and Dirac fields
• Gravitationally induced inhibitions of dispersion according to the Schrödinger-Newton Equation
• Notes on Certain Newton Gravity Mechanisms of Wave Function Localisation and Decoherence
• How Stands Collapse II
• On the Energy Increase in Space-Collapse Models
• A discrete model of energy-conserved wavefunction collapse
• On Diósi-Penrose criterion of gravity-induced quantum collapse

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