Timeline for Quantum entanglement from different frames of reference and the conservation laws
Current License: CC BY-SA 4.0
8 events
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| May 28 at 15:43 | comment | added | DrChinese | @Rekkhan Sorry about that, I can explain. I use basis and measurement basis interchangeably. When you measure polarization at some angle, that is a basis. So 0, 30, 45, 90 degrees are all bases. Also momentum and position have a basis. If you measure both entangled particles at 30 degrees, the value you get for one will allow you to predict the other with certainty. That fits with your idea. But that doesn’t apply in all cases, such as when you measure one on the 30 degree basis and the other on the 150 degree basis. This is a measurement context in which classical ideas start to break down. | |
| May 28 at 7:48 | comment | added | Rekkhan | I definitely don't understand your last message starting from the 3rd sentence. I'm not a theorist so your explanation is quite abstract for me. May I ask what is the basis you are mentioning? | |
| May 27 at 15:17 | comment | added | DrChinese | @Rekkhan By classical logic, you may correctly deduce the outcome of a measurement on B after learning the outcome on A. Experiment will confirm. But that is only true for a very specific measurement basis for both: that being both on the same basis. That's a special case! The general prediction is actually a function of both the basis of A and the basis for B. That's called the context, which is a combination of the future basis for A and B. Time and ordering is not a factor at all in that function. This nuance is not obvious, as we learned from the EPR (1935) & Bell (1964) papers | |
| May 27 at 9:12 | comment | added | Rekkhan | A question if you don't mind. From my understanding, the states of the entangled particles are "glued" together, thus measuring one means measuring both, am I really deducing something without measuring? (to be honest, I don't know if we can do any other measurement in this case) | |
| May 26 at 16:26 | comment | added | DrChinese | @Rekkhan Fair enough. However, you immediately run afoul of a common quantum mechanical miscue - reasonable as it might be. That being: trying to deduce what is occurring between measurements. (Peres: "unperformed measurements have no results:.) QM says the final measured result will not violate a conservation rule. You must consider the final full measurement context. There are many quantum scenarios in which "logical deductive reasoning" falls apart, and this is one. (Hopefully you would agree that reference frame cannot be a factor.) | |
| May 26 at 1:23 | comment | added | Rekkhan | when I said violation, I mean while a particle has its spin, for example, observed, the other one is still in superposition, thus spin conservation is violated. I'll update my question to make it clearer. | |
| May 25 at 19:56 | history | edited | DrChinese | CC BY-SA 4.0 |
added 66 characters in body
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| May 25 at 19:51 | history | answered | DrChinese | CC BY-SA 4.0 |