Localization and Entanglement in Relativistic Quantum Physics

Luca Lusanna

Luca Lusanna

After a review of the problems induced by the Lorentz signature of Minkowski space-time, like the need of a clock synchronization convention for the definition of 3-space and the complexity of the notion of relativistic center of mass, there is the introduction of a new formulation of relativistic quantum mechanics compatible with the theory of relativistic bound states. In it the zeroth postulate of non-relativistic quantum mechanics is not valid and the physics is described in the rest frame by a Hilbert space containing only relative variables. The non-locality of the Poincare' generators imply a kinematical non-locality and non-separability influencing the theory of relativistic entanglement and not connected with the standard quantum non-locality.

Jeffrey Alan Barrett

Andrea Di Biagio, Richard Howl, Časlav Brukner +2 more

Locality is a central notion in modern physics, but different disciplines understand it in different ways. Quantum field theory focuses on relativistic locality, based on spacetime regions, while quantum information theory focuses circuit locality, based on the notion of subsystems. Here, we investigate how spacetime and subsystem locality are related in the context of systems getting entangled while interacting via a scalar field. We show how, when the systems are put in a quantum-controlled superposition of localised states, relativistic locality (in the form of microcausality) gives rise to a specific kind of circuit. The relation between these forms of locality is relevant for understanding whether it is possible to formulate quantum field theory in quantum circuit language, and has bearing on the recent discussions on low-energy tests of quantum gravity.

F.J. Duarte, T S Taylor

Leonardo Ruiz González

The empirical violation of Bell’s inequality shows that the relativistic speed limit is incompatible with the quantum entanglement. ‘Proper Present Interpretation’ shows a local relativistic theory without using hidden variables that is consistent with quantum entanglement. The method used is a change of present. For every observer, his present in each moment is the universe he observes. It involves a change of coordinates. It is explained quantum problems related to quantum entanglement such as Einstein–Podolsky–Rosen paradox, ‘Schr¨odinger’s cat’ and the Young’s double-slit experiment. Are obtained simpler equations for the relativistic transformations of physical magnitudes by using the same transformation in all cases. With this new concept, quantum and relativistic mathematics keep being both valid and stop being mutually exclusive in relation to the concept of locality. The results suggest a relational space-time reality.