An operational approach to spacetime symmetries: Lorentz transformations from quantum communication

Understand

In most approaches to fundamental physics, spacetime symmetries are postulated a priori and then explicitly implemented in the theory.

• This includes Lorentz covariance in quantum field theory and diffeomorphism invariance in quantum gravity, which are seen as fundamental principles to which the final theory has to be adjusted.
• In this paper, we suggest, within a much simpler setting, that this kind of reasoning can actually be reversed, by taking an operational approach inspired by quantum information theory.
• We consider observers in distinct laboratories, with local physics described by the laws of abstract quantum theory, and without presupposing a particular spacetime structure.