> What's the current status of Bohm's hidden variable theory? Does it stand up in light of the Bell test
In "normal" quantum mechanics we have the wave-particle dualism. A particle behaves also like a wave, whatever that means.
In Bohm's hidden variable theory, also known as "pilot wave theory" the wave and the particles are separate. The pilot wave is a wave of unknown making (the theory does not say what it would be made of), and this wave follows the normal quantum mechanical behaviour. Then particles "ride" on this wave. So all the quantum mechanical wave effects happen in the pilot wave, and then the classical particle-like particles just follow theirs paths, already laid out by the wave.
Although "spooky action at a distance" is also experimentally verified, explaining this by postulating a wave that fills the whole universe, and explicitly reacts spookily over distances, makes the whole "spooky action at a distance" uncomfortable explicit in this theory, so it doesn't appeal to most physicists.
"The de Broglie–Bohm theory makes the same (empirically correct) predictions for the Bell test experiments as ordinary quantum mechanics. It is able to do this because it is manifestly nonlocal."
In "normal" quantum mechanics we have the wave-particle dualism. A particle behaves also like a wave, whatever that means.
In Bohm's hidden variable theory, also known as "pilot wave theory" the wave and the particles are separate. The pilot wave is a wave of unknown making (the theory does not say what it would be made of), and this wave follows the normal quantum mechanical behaviour. Then particles "ride" on this wave. So all the quantum mechanical wave effects happen in the pilot wave, and then the classical particle-like particles just follow theirs paths, already laid out by the wave.
Although "spooky action at a distance" is also experimentally verified, explaining this by postulating a wave that fills the whole universe, and explicitly reacts spookily over distances, makes the whole "spooky action at a distance" uncomfortable explicit in this theory, so it doesn't appeal to most physicists.
"The de Broglie–Bohm theory makes the same (empirically correct) predictions for the Bell test experiments as ordinary quantum mechanics. It is able to do this because it is manifestly nonlocal."
http://en.wikipedia.org/wiki/De_Broglie%E2%80%93Bohm_theory#...