How Does Rotating the Local Basis Affect Quantum Entanglement of Photons?

fulis
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A question came up about entanglement and I've only studied very little QM so far, so I went to wikipedia to see if I could become any wiser and they had an example on photon entanglement which was quite straight forward (though the whole page lacks sources =[ ). The example shows that if you have photons going in opposite directions and that are entangled such that they will have the same polarization and their state is a superposition of vertical and horizontal polarization states then they actually don't have a polarization. Kind of a neat result.

Anyway, I figured I'd try to change the example a bit by having the two photons have opposite polarizations instead, so instead of the state:
|1,V>|2,V>+|1,H>|2,H>
I used:
|1,V>|2,H>+|1,H>|2,V>

I did the exact same substitution for the V and H states as they did in the example. I was expecting to get:
|1,45>|2,135>+|1,135>|2,45> since the photons are entangled in such a way that they have opposite polarization, but instead I got (I haven't normalized any of these expressions):
|1,45>|2,45>-|1,135>|2,135>

which is contradictory to the entanglement. The actual calculation is really simple and I did double check it a few times so I'm guessing the problem is something else. It's not exactly the best written wiki entry so I don't trust it to be right :D if someone else could show me how you actually calculate it I'd be grateful
 
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You'll have to be more precise... |1V>|2H> + |1H>|2V> seems to me like a perfectly formed quantum state of two photons (modulo normalization, of course). Why do you rotate the local basis?
 
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I am not sure if this belongs in the biology section, but it appears more of a quantum physics question. Mike Wiest, Associate Professor of Neuroscience at Wellesley College in the US. In 2024 he published the results of an experiment on anaesthesia which purported to point to a role of quantum processes in consciousness; here is a popular exposition: https://neurosciencenews.com/quantum-process-consciousness-27624/ As my expertise in neuroscience doesn't reach up to an ant's ear...
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