Where is the flaw with predetermined entanglement state?

[zonde]

Please note that that was not MY interpretation. If you read those papers that I referenced to, there is a clear reference to realism and what they are testing.

I read very carefully your reference about Wheeler's delayed-choice experiment with helium atoms. I could not find anything similar to your statement.
The best bet would be this:
"Wheeler's thought experiment is important since it tries to force a classical view of reality on to a quantum system."
It is quite a stretch by itself and yet it does not go as far as your statement.

The fact that "realism", as defined within this context, can actually be tested experimentally means that it has been brought out of philosophy and into physics

You can of course use the same word in physics as used in philosophy but it's confusing and I would say it's attempt to do philosophy disguised as physics.

Say we use some "word" in one sense. I redefine the "word" in different sense and falsify it in this second sense. Then I claim that "word" is falsified while the "word" is generally understood in first well established sense and is obviously not falsified in that first sense. Do you see the fallacy?

 

[ZapperZ]

Fact check: what do you think is the definition of "realism" as used here in theses PHYSICS papers and the one being addressed in Leggett inequality?

Zz.

 

[zonde]

However, a more limited view of science is that it is about making predictions, of the form: If I perform such and such an experiment, I will get such and such result. That limited view of science doesn't require realism.

In some idealized sense your argument is valid but ... scientific model contributes to knowledge of society when you can share it (communicate it), share results of experimental tests, repeat experiments and such things. It all relies on realism.
Besides new model would most certainly rely a lot on existing knowledge in order to make predictions (experimental equipment, design of experiment). Can you review all existing knowledge in light of some non-realistic model? Say we have arrived at existing knowledge by throwing out non-realistic models. You can't really review all discarded models.

 

[Derek Potter]

If you are talking about Leggett's definition of realism, which is a technical one, I don't know.

Nothing so specific. I'm just groping towards understanding what a real but non-local model could mean. I don't seem to be getting very far. No matter, I'll brush up on BM after I've fixed the measurement problem in MWI At least I have an idea of what I'm up against now, thanks.

 

[zonde]

Fact check: what do you think is the definition of "realism" as used here in theses PHYSICS papers and the one being addressed in Leggett inequality?

There is no definition of realism in paper about Wheeler's delayed choice experiment as word "realism" is not used there at all.
I don't know about Leggett inequalities but I suppose it's some sort of realism that requires that particle observables are determined by non-contextual variables (and that allows non-locality).

 

[ZapperZ]

Then maybe, BEFORE you attack, that you understand the definition that has been used when we talk about "realism" in physics AND in the context that of this topic. I had been explicit in invoking the Leggett formalism here, which I thought was sufficient to clarify the exact definition of what I was referring to. To hear now that you didn't even bother to figure that out and yet were quick to criticize on it is ridiculous.

In case you are too lazy to look, these things have been posted elsewhere already:

https://www.physicsforums.com/threads/recent-noteworthy-physics-papers.127314/page-4#post-1599072
https://www.physicsforums.com/threads/recent-noteworthy-physics-papers.127314/page-2#post-1307660

Zz.

 

[zonde]

Then maybe, BEFORE you attack, that you understand the definition that has been used when we talk about "realism" in physics AND in the context that of this topic. I had been explicit in invoking the Leggett formalism here, which I thought was sufficient to clarify the exact definition of what I was referring to. To hear now that you didn't even bother to figure that out and yet were quick to criticize on it is ridiculous.

Let me repeat this particular question:

Say we use some "word" in one sense. I redefine the "word" in different sense and falsify it in this second sense. Then I claim that "word" is falsified while the "word" is generally understood in first well established sense and is obviously not falsified in that first sense. Do you see the fallacy?

 

[atyy]

Nothing so specific. I'm just groping towards understanding what a real but non-local model could mean. I don't seem to be getting very far. No matter, I'll brush up on BM after I've fixed the measurement problem in MWI At least I have an idea of what I'm up against now, thanks.

BM is realistic in the common sense classical physics way. There is a subtlety as to whether the "wave function" in BM is real or not, since there is more than one wave function, but to start we can ignore that. BM is nonlocal in the sense that the wave function in QM is nonlocal, since it is in Hilbert space. The position of a particle depends on the wave function, so it is nonlocal. Basically, QM itself is nonlocal, if the wave function is taken to be real. BM takes over this nonlocality and solves the measurement problem by introducing hidden variables, so that there is naive reality and an observer is not required to determine what is real.

 

[Drakkith]

Thread locked, pending moderation.