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Bell's therorem seems to disprove localism because measuring, let's say spin of an entangled electron, seem to communicate the measurement to it's another pair instantaneously.

But isn't another thing possible?

Maybe the electrons are not communicating anything and instead the two instruments which are measuring the electrons "know" at what angle the other instrument is measuring the other electron and that is a part of the measuring process of instrument and thus the Bell's equality is violated but local realism is still valid. Here the two instruments and the people who are performing the experiments are in some kind of weird sync where they cannot measure arbitrarily in any direction but instead the measurement angles are predetermined before hand and the instruments already know the angles with of each other which are used to measure, hence the spin directions can be correlated. This would mean that Universe is deterministic but also locally real.

Is this at least theoretically possible? If it is possible wouldn't it be more saner theory to adopt rather than throwing local realism away? Why? Why not?

Hari Kumar
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Maybe the electrons are not communicating anything and instead the two instruments which are measuring the electrons "know" at what angle the other instrument is measuring the other electron

The problem with that is that you don't have to make the decision about which way to measure it until the moment of measurement, and in that case how can the two instruments 'know'? You are simply replacing FTL-communicating electrons with FTL-communicating measurement instruments.

They also did an experiment where the choice of which direction to measure was decided by the light from two distant quasars on opposite sides of the universe, for which there is no sub-lightspeed way for them to have communicated. It still worked.

'Superdeterminism' is a logically possible alternative, but effectively abdicates any need for explanation, which negates the whole purpose of physics.

But isn't another thing possible?

Oh, yes. If you throw away the assumption that the macroscopic world obeys different rules and that the wavefunction collapses, and instead take seriously the idea that the rules of quantum mechanics known to work at the microscopic level are in fact universal, you find you get a theory that explains our observation of a 'classical' world, as well as all those entangled long-distance quantum correlations, while being entirely local, deterministic, and realist. That's the Everett Interpretation.

Yeah even if the sync is left unexplained wouldn't it be still a better alternative than "spooky action at a distance"??

You would think so, wouldn't you?

Nullius in Verba
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