Many “pseudo-paradoxes” arise in quantum physics because “quantum states” are generally considered to be absolute, that is, independent of observers. But entangled pairs of qubits in Bell states with two distant observers, one per qubit, force us to reconsider the status of quantum states, revealing their observer-dependence. It is at the core of the “relational” interpretation of quantum mechanics, as proposed by Carlo Rovelli [Rovelli 1996], or Asher Peres’ interpretation of the Einstein-Podolsky-Rosen dilemma [Peres 2004, §2],
and it is related to the observer-dependence of time in special relativity. It is important to have in mind this observer-dependence in distributed quantum systems, such as quantum networks where the speed of light cannot be considered as “infinite”. It helps in understanding and accepting the physical phenomena involved in such systems.
References:
- (“easy” to read, mostly philosophical views on quantum physics)
[Rovelli 1996] Carlo Rovelli, Relational Quantum Mechanics, 1996
https://arxiv.org/abs/quant-ph/9609002 - [Peres 2004] Asher Peres, Quantum information and general relativity, 2004
https://arxiv.org/abs/quant-ph/0405127
Slides of the presentation: PDF.