I Bell's Theorem and Reality

  • Thread starter facenian
  • Start date

stevendaryl

Staff Emeritus
Science Advisor
Insights Author
8,400
2,572
It is not that Superdeterminism is "impossible", it is just that, it is so "ad hoc" that it really explains NOTHING (and of course it predicts nothing in general, so, it is mostly useless).

And yes, I know t'Hooft is working on a Superdeterminism model of Physics, but still.....
Actually, superdeterminism is not a theory, it's a feature of a theory. And as far as I know, there is no plausible theory that has that feature.
 
387
14
It is not that Superdeterminism is "impossible", it is just that, it is so "ad hoc" that it really explains NOTHING (and of course it predicts nothing in general, so, it is mostly useless).
I agree, I feel it is similar to discussing God's existence in scientific terms
 
479
10
It is not that Superdeterminism is "impossible", it is just that, it is so "ad hoc" that it really explains NOTHING (and of course it predicts nothing in general, so, it is mostly useless).

And yes, I know t'Hooft is working on a Superdeterminism model of Physics, but still.....
A minimalist version of superdeterminism only requires a denial of statistical independence assumption between detector settings and the spins of emitted particles. In order for this assumption to fail it is enough to show that some physical states of the detectors are incompatible with some physical states of the particle source. Take any mainstream field theory, like classical EM and write down the states. For this particular example the states will contain position and momenta of all charged particles inside the detectors and source (electrons and nuclei, or quarks if you like) as well as magnetic and electric field vectors. It is obvious that most states will not be compatible (like a net positive charge at detector A and a null electric field at the source) so the statistical independence assumption fails. Can you point out any ad-hoc assumption in the above argument?
 
479
10
Actually, superdeterminism is not a theory, it's a feature of a theory. And as far as I know, there is no plausible theory that has that feature.
Please see my above post. Pretty much all field theories have that feature ('t Hooft's CA interpretation is an example of a discrete field theory).
 

stevendaryl

Staff Emeritus
Science Advisor
Insights Author
8,400
2,572
Please see my above post. Pretty much all field theories have that feature ('t Hooft's CA interpretation is an example of a discrete field theory).
No, field theories do not have that feature. Field theories are deterministic, but not superdeterministic.

The distinction is illustrated by an EPR-type experiment. Consider the question of predicting, for an EPR-type experiment, what detector setting Alice is going to choose in the future. If Alice's choice is governed by deterministic physics, then it is predictable given her past lightcone. But I don't have access to her entire past lightcone.

superdeterministic.jpg


This is illustrated by the picture. The red region is Alice's past lightcone. The yellow region is my past lightcone. The orange region is our shared causal past. Alice's choice could depend on anything in the red region or orange region. But if I'm trying to predict Alice's choice, the only information I have is the orange region. So in general, I do not have enough information to predict Alice's choice.

So Alice's choices are not predictable by me, even if they are deterministic.
 

Attachments

Last edited:
191
36
A minimalist version of superdeterminism only requires a denial of statistical independence assumption between detector settings and the spins of emitted particles. In order for this assumption to fail it is enough to show that some physical states of the detectors are incompatible with some physical states of the particle source. Take any mainstream field theory, like classical EM and write down the states. For this particular example the states will contain position and momenta of all charged particles inside the detectors and source (electrons and nuclei, or quarks if you like) as well as magnetic and electric field vectors. It is obvious that most states will not be compatible (like a net positive charge at detector A and a null electric field at the source) so the statistical independence assumption fails. Can you point out any ad-hoc assumption in the above argument?
The problem is about usefulness.

Could you (or anybody else) have predicted (based on a Superdeterminism model) the experimental results in Bell type tests (and infinitely many other possible different tests) if QM didn't exist (had we never discovered QM) ?

I have seen some papers trying to obtain KNOWN experimental results (that QM predicts correctly) based on Superdeterminism models, but every time it is "adapted" to the known result, it is never a prediction, not even a "natural" or "general" model, but it is totally conceived to just match that previous known result and nothing else.
 
191
36
I'm not sure who you're talking to, but I disagree with both of these assertions. As I said, superdeterminism is a feature of a theory, it's not a theory. A superdeterministic theory might very well be testable and useful. But we don't currently have an example of one.

I actually don't think that t'Hooft's automata is a definitive example. He hasn't shown that such automata can plausibly reproduce EPR-type experiments.
I was responding to ueit, but now I am interested in your position.

Do you think we are ever going to find a Superdeterministic model that can actually predict, for example, our choices about instrumental settings?

It is not impossible in principle, but I highly doubt it.
 
191
36
Ummm, some messages have suddenly dissappeared, what happened?
 

Nugatory

Mentor
12,326
4,802
Ummm, some messages have suddenly dissappeared, what happened?
One post was removed for a rules violation; and then the posts replying to it, including one of yours, were removed because they no longer had any context. You should have received an alert telling you this happened (if you didn't, it's because I accidentally didn't check the box to make that happen, and I apologize).
 
191
36
Ah, no problem, I was just curious. But....is it allowed here to talk about Superdeterminism anyway?
 

Nugatory

Mentor
12,326
4,802
Ah, no problem, I was just curious. But....is it allowed here to talk about Superdeterminism anyway?
Yes. That's not a problem.
 
387
14
I was responding to ueit, but now I am interested in your position.

Do you think we are ever going to find a Superdeterministic model that can actually predict, for example, our choices about instrumental settings?

It is not impossible in principle, but I highly doubt it.
Is there any difference between this superdetermism and the phylosophical doctrine of fatalism or predeterminism? If not I find it hard to discuss these things in scientific terms at least for the moment. May in the future who knows. Not so long ego it was not possible to talk about the origin of the universe in scientific terms.
 

stevendaryl

Staff Emeritus
Science Advisor
Insights Author
8,400
2,572
I was responding to ueit, but now I am interested in your position.

Do you think we are ever going to find a Superdeterministic model that can actually predict, for example, our choices about instrumental settings?

It is not impossible in principle, but I highly doubt it.
I highly doubt it, as well. But I don't completely dismiss the possibility. The reason I don't is because there is a sense in which superdeterminism is no weirder than the thermodynamic arrow of time. Maybe understanding the latter might change our view of what is plausible or implausible.
 

Want to reply to this thread?

"Bell's Theorem and Reality" You must log in or register to reply here.

Related Threads for: Bell's Theorem and Reality

Replies
220
Views
12K
Replies
16
Views
1K
  • Posted
Replies
4
Views
2K
  • Posted
9 10 11
Replies
264
Views
23K
Replies
5
Views
7K
Replies
5
Views
983
Replies
115
Views
19K

Physics Forums Values

We Value Quality
• Topics based on mainstream science
• Proper English grammar and spelling
We Value Civility
• Positive and compassionate attitudes
• Patience while debating
We Value Productivity
• Disciplined to remain on-topic
• Recognition of own weaknesses
• Solo and co-op problem solving

Hot Threads

Top