Experimental metaphysics was born from Bell’s theorem, and the experiments it inspired, that prove the world cannot be both local and deterministic. There is an implicit assumption here, that an experimenter sees a definite outcome when (s)he measures a system, which is brought into question when the experimenter becomes a system (the “Wigner’s Friend” scenario). We have derived a new theorem for this scenario, which is similar to Bell’s theorem but which does without determinism. I will present experimental results where the “friend system” is a single qubit. However, I claim, for a truly convincing experiment, that system would have to be a quantum computer large enough, and running sufficiently advanced AI software, that it could be regarded genuinely as a friend.

# CAN A QUBIT BE YOUR FRIEND? Why a philosopher would want to have a quantum computer

Host: Aephraim Steinberg