Does entanglement violate special relativity?

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DrChinese

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A fundamental theory that is deterministic is necessary superdeterministic. A deterministic theory at a fundamental level allowing "independent decisions of experimenters" is logically contradictory, therefore it makes no sense to seriously speak about it.
This is inaccurate, determinism does NOT imply superdeterminism. Even if my decisions are predetermined, that does not mean that the Bell Inequality will be violated by my choices of measurement settings - which is the premise of superdeterminism.

Your superdeterminism is supposed to explain something, and it doesn't. Every particle would need to have all the details of all other particles contained locally to work. We have previously discussed this point in other threads, and concluded that superdeterminism has baggage. Further debate of superdeterminism here would be off-topic.
 
We are drifting off into superdeterminism. Read the thread title.

One example of 'instant something' is the collapse of the wave function in every path of a split beam or all over a spherical surface created by a photon spreading out. When a photon is observed then 'it knows' its been observed at every possible place the wave function could be - instantly.

Although its a negative its as strange as correlation 'exchanges' & probably for the same reason. - For me its about information in information space, so I see no problem, but for the rest of you.... boy, do you have problems!
 
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I dont have problems, I believe in MWI.
The hardest thing of all is to find a black Shroedinger's cat in a dark room, especially if there is no wavefunction collapse.
 

Demystifier

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The only thing you need is the wave function at Big Bang and particle configuration at Big-Bang.
Yes, but the many-particle wave function at the initial time is still a non-local object, the time evolution has nothing to do with it. Since it is a many-particle wave function, you cannot specify it by specifying psi at each point of space. Instead, for 2 particles you need to specify psi for each PAIR of points on space, and similarly for n particles. This is why it is a nonlocal object even without the time evolution. You probably want to say that there is no nonlocal force, but my point is that there is nonlocal - something.
 
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Wrong
It is true only if you assume (like most people do) "single history" which is not a case in MWI
No, MWI is superdeterministic. Once universal wavefunction is specified everything folows. A single branch is not superdeterministic but MWI is not about a single branch.
 

Demystifier

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This is inaccurate, determinism does NOT imply superdeterminism. Even if my decisions are predetermined, that does not mean that the Bell Inequality will be violated by my choices of measurement settings - which is the premise of superdeterminism.
The point is that predetermined choices are not choices at all. Instead, your arms MUST make the measurement settings that will provide violation of Bell inequalities.
 
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No, MWI is superdeterministic. Once universal wavefunction is specified everything folows. A single branch is not superdeterministic but MWI is not about a single branch.
In "bird's view", yes
But for an observer reality looks random
So we agreed on it...
 
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No, MWI everything can start from an empty space, for example 0
Then there are fluctuations, you get 01 and 10 branches
In each area of space fluctuations ddmore and more entropy: 0001, 0010, 0101, ... etc.
System becomes more and more complex
As far as I know MWI starts with a wavefunction. That wavefunction evolves deterministicaly in accordance with Schroedinger's equation. You should explain what do you mean by "empty space" and "fluctuations" in this context.
 

Demystifier

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Demystifier

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The return of Laplace determinism :)
particle configuration at Big-Bang defines what I am going to type right now.
Imagine that it is right. Doesnt it mean that the entropy at Big bang was VERY HIGH, contrary to what we know about it?
No, it doesn't. Nature may choose initial conditions that have a small entropy.
 
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This is inaccurate, determinism does NOT imply superdeterminism. Even if my decisions are predetermined, that does not mean that the Bell Inequality will be violated by my choices of measurement settings - which is the premise of superdeterminism.
I don't think Bell Inequality is a premise of superdeterminism. At least in my understanding, superdeterminism is determinism applied globally, to the entire system of interest. Saying that a part of a system evolves deterministically while another is allowed free choices is logically absurd. IMHO, the so-called weirdness of QM has its roots in this absurdity.

Your superdeterminism is supposed to explain something, and it doesn't. Every particle would need to have all the details of all other particles contained locally to work. We have previously discussed this point in other threads, and concluded that superdeterminism has baggage. Further debate of superdeterminism here would be off-topic.
You are the one who started this debate on Bell Inequality here. To stay on topic I will not continue it further. My point was strictly related to the issue of non-locality in the context of a deterministic theory, not about how Occam-friendly this or that interpretation is. anyway, I didn't agreed to your conclusion "superdeterminism has baggage", that's your opinion only.
 

Demystifier

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Although its a negative its as strange as correlation 'exchanges' & probably for the same reason. - For me its about information in information space, so I see no problem, but for the rest of you.... boy, do you have problems!
Does it mean that you accept the idea that nothing really exists except information?
 

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DrChinese

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I fully agree! Indeed, there is a theorem that confirms this (in QM):
http://xxx.lanl.gov/abs/quant-ph/0604079
That seems a weird reference for you to agree with... they claim it rules out all deterministic theories (including Bohmian/dBB type) other than superdeterministic ones. Nice paper, by the way, covers a lot of interesting ground.
 
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As far as I know MWI starts with a wavefunction. That wavefunction evolves deterministicaly in accordance with Schroedinger's equation. You should explain what do you mean by "empty space" and "fluctuations" in this context.
Based on the current cosmological model, we had an inflation era. During that time space was empty (sort of vacuum). Then vacuum started to decay giving life to 'particles'

What is important is that during that time the first fluctuations appear... is some places there were MORE particles then in another places. For that reason we have galaxies somewhere while other space is almost empty.

So how could a state of universe where all points of space were in the same state (empty, vacuum) could evolve into another state where in SOME places there was MORE matter then in another ones?

To allow such symmetry breaking theory must be non-deterministic (CI for example) or multi-history (MWI allows to break symmetry deterministically, breakig it differently in different worlds).

Deterministic single-history theory can not, in principle, convert a state with low entropy (like empty space) into something complex, like what we observe.
 
Special relativity (SEE THREAD TITLE)
is an information rule that must apply
for a field model of the universe to work.
Otherwise cause and effect would mess up.
But no particles are separated at all.

This is more like what it 'looks like':

10101011110010101001001110010010001
11101001001010100100010101010101010
10101010010001000111110110100001111
10101011110010101001001110010010001
11101001001010100100010101010101010
10101010010001000111110110100001111
10101011110010101001001110010010001
11101001001010100100010101010101010
10101010010001000111110110100001111
10101011110010101001001110010010001
11101001001010100100010101010101010
10101010010001000111110110100001111
10101010010001000111110110100001111
10101011110010101001001110010010001
11101001001010100100010101010101010
10101010010001000111110110100001111
10101011110010101001001110010010001

The above is information space (in bits not
Qubits which I cannot show) which has
both our entangled particles in it (We also
live in there, 3 D space is created in it
- as Newton said - the universe was created with numbers,
- 3 D space is a total illusion, but a good one).
 
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Special relativity (SEE THREAD TITLE)
is an information rule that must apply
for a field model of the universe to work.
Otherwise cause and effect would mess up.
But no particles are separated at all.

This is more like what it 'looks like':

10101011110010101001001110010010001
11101001001010100100010101010101010
10101010010001000111110110100001111
10101011110010101001001110010010001
11101001001010100100010101010101010
10101010010001000111110110100001111
10101011110010101001001110010010001
11101001001010100100010101010101010
10101010010001000111110110100001111
10101011110010101001001110010010001
11101001001010100100010101010101010
10101010010001000111110110100001111
10101010010001000111110110100001111
10101011110010101001001110010010001
11101001001010100100010101010101010
10101010010001000111110110100001111
10101011110010101001001110010010001

The above is information space (in bits not
Qubits which I cannot show) which has
both our entangled particles in it (We also
live in there, 3 D space is created in it
- as Newton said - the universe was created with numbers,
- 3 D space is a total illusion, but a good one).
This computers not physics. Read Quantum Field Theory and Quanum Mechanis.
 
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A fundamental theory that is deterministic is necessary superdeterministic. A deterministic theory at a fundamental level allowing "independent decisions of experimenters" is logically contradictory, therefore it makes no sense to seriously speak about it.
No. A deterministic theory allows to explain the observables in terms of some sufficiently small subsets of the state of the universe, so that one can introduce a notion of causality as well as of independence. There is no contradiction at all. Simply in some deterministic theories some events do not depend on the whole universe one minute ago, but only on some small part of the universe one minute ago.
 

Demystifier

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That seems a weird reference for you to agree with... they claim it rules out all deterministic theories (including Bohmian/dBB type) other than superdeterministic ones. Nice paper, by the way, covers a lot of interesting ground.
It does not rule out Bohmian/dBB type theories because such theories are naturally interpreted as superdeterministic (provided that the notion of "superdeterministic" is understood appropriately).
 

Demystifier

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Deterministic single-history theory can not, in principle, convert a state with low entropy (like empty space) into something complex, like what we observe.
Man, what are you talking about? :eek:
An obvious counter-example to your claim is classical mechanics of many degrees of freedom, where entropy is understood as the coarsegraining entropy.
 
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Sorry, I meant some specific examples of entropy increase.

I should say
'Deterministic single-history theory can not, in principle, break a symmetry, for example, convert an empty space (empty everywhere) into space where somehwere there are stras, planets, while in the other parts space is void'
 
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Any way to FTL with entangled system?

I believe the answer is no. But I have some doubts.

Assume we create every microsecond an entangled spin pair, for a total of 1000000 pairs.
Assume we will measure the entangled pairs when they are separated by 1 lightyear!
Assume the measuring device on side A will measure 0.1 microseconds before the measuring device on the other side B.
Assume the spin orientation on side A can be chosen freely for each individual measurement.

I have the intuiton that it would be possible to sent a few bits of information (say one bit) from A to B at a Faster Than Light speed. But this transfer would not be totally reliable. The reliability would increase with the number of pairs analysed as well as with the ingeniosity of the experimenter.

Am I dreaming?
 

alxm

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Re: Any way to FTL with entangled system?

I have the intuiton that it would be possible to sent a few bits of information (say one bit) from A to B at a Faster Than Light speed.
How did your particles get separated at FTL speed?
Or were they separated at the start? If they were, how did they become entangled? That requires them to interact with each other. How did they interact at FTL speed?
 

DrChinese

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It does not rule out Bohmian/dBB type theories because such theories are naturally interpreted as superdeterministic (provided that the notion of "superdeterministic" is understood appropriately).

In superdeterminism, the choice of an experimenter's measurement setting is controlled by initial conditions in just such a way as to allow Bell's Inequality to be violated. In strict determinism, the experimenter's choice of measurement setting is not "free", but Bell's Inequality is not violated as a postulate of the theory. Instead, there is some other mechanism (in your case non-locality) which is responsible.
 
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Re: Any way to FTL with entangled system?

How did your particles get separated at FTL speed?
Or were they separated at the start? If they were, how did they become entangled? That requires them to interact with each other. How did they interact at FTL speed?
Just as in the Alain Aspect experiment, just on a longer scale for the story.
Two entangled photons traveling in opposite ways, and the experimenter waiting long enough.
 

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