Test of Bell's Theorem: Experiments Beyond Polarization

[Dadface]

As I understand it most, if not all, experiments carried out to test Bells theorem test the local hidden variables assumption that photons have definite polarisations. What I would like to know is whether experiments on properties other than polarisation have been carried out. If not are there any properties that in principle can be tested? Thank you for reading this.

 

[DrClaude]

What I would like to know is whether experiments on properties other than polarisation have been carried out.

Yes: http://www.nature.com/nature/journal/v461/n7263/full/nature08363.html

 

[DrClaude]

Here's another one: http://dx.doi.org/10.1126/science.aad8665

 

[DrChinese]

As I understand it most, if not all, experiments carried out to test Bells theorem test the local hidden variables assumption that photons have definite polarisations. What I would like to know is whether experiments on properties other than polarisation have been carried out. If not are there any properties that in principle can be tested?

As DrClaude has said, there are others. In fact, probably at least a hundred other tests of local realism (local hidden variables) that have been made on photons, as well as all manner of other systems. Virtually any kind of entanglement leads to an inequality, and I see new ones all the time. It's really just a question of how many and/or how different/unique/interesting you want to see. Here's a few more:

Massive entangled particles (9Be+ ions)
http://www.nature.com/nature/journal/v409/n6822/full/409791a0.html

Two ultracold neutral atoms
https://arxiv.org/abs/1507.05586

Light-matter micro-macro entangled state
https://arxiv.org/abs/1510.02665

 

[Dadface]

Thank you very much DrClaude and DrChinese. Am I correct in assuming that all of these experiments test the local realism assumption that light or macro particles or whatever it is being investigated have definite properties?

 

[DrChinese]

Thank you very much DrClaude and DrChinese. Am I correct in assuming that all of these experiments test the local realism assumption that light or macro particles or whatever it is being investigated have definite properties?

Yes and no. The properties being tested are a quantum observable of some type. Besides the usual position, momentum, spin, etc there are some that are composite in some manner.

And the test assumes the observable exists independent of the act of observation. I.e. that it is non-contextual, which is to say realistic in this usage of the term.

 

[Dadface]

Great stuff, thank you DrChinese.