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  4. Please Clarify Quantum Entanglement?
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Please Clarify Quantum Entanglement?

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Offline JP

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Re: Please Clarify Quantum Entanglement?
« Reply #20 on: 25/05/2013 16:54:06 »
Quote from: dlorde on 25/05/2013 15:40:43
Quote from: Bill S on 25/05/2013 15:02:05
I assume you mean the example with the coins. I see the analogy, but don't see how it avoids hidden variables.
It's just an analogy for how it appears to the observer, nothing to do with hidden variables.

The problem is that entanglement has no classical counterpart.  Real-world coins are classical, and there is no such thing as a pair of coins that is in two states simultaneously until you measure it.  Real-world classical coins would either be in one state or the other before you peek, even if you don't know which--which is hidden variables.  I wish I could come up with a simple analogy to the fact that quantum particles appear to literally be in two states at once, but that measurement seems to "choose" only one of those states, but I don't really know of one. 

If you know quantum mechanics well enough, entanglement isn't all that odd.  The two entangled particles are a single quantum object and we know quantum objects can be in more than one state at a time, so there's no problem with having a state that's heads/heads+tails/tails.  When you measure something in quantum mechanics, you can force it to "choose" one of those possibilities, either heads/heads or tails/tails.  Since it's a single quantum object, there's nothing weird with it choosing one of those states.  The problem is that we tend to think of those two coins as somehow independent, when in QM, it's really the entire state of both coins that's the object of interest.
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Offline yor_on

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Re: Please Clarify Quantum Entanglement?
« Reply #21 on: 25/05/2013 17:16:06 »
In relativity you can't have something happening simultaneously unless they are perfectly 'at rest' with each other, in a same absolute 'frame of reference', everything describing those two relative a observer the exact same. In QM? Not sure how that should be defined? Assuming it can be, you still should have two choices. Either you use a 'hidden parameter', in which case the names are set before measuring, or you use quantum logic (as well as Bells theorem) defining it, in which case you still should see it 'instantly', as I think, and as JP describes it.
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Offline CPT ArkAngel

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Re: Please Clarify Quantum Entanglement?
« Reply #22 on: 25/05/2013 18:08:53 »
Superposition of states for one particle has never been proved and will never be, by QM definition. The act of measurement is the act of entanglement. The entire universe is a superposition of states that we perceive through interactions in space and time...

I don't understand how people can follow a path that leads to nowhere... Refusing to follow other paths is giving up the search for a deeper truth... One day, not so far, you will all change your mind...
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Offline Bill S

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Re: Please Clarify Quantum Entanglement?
« Reply #23 on: 25/05/2013 22:58:14 »
Quote from: CPT ArkAngel
The entire universe is a superposition of states that we perceive through interactions in space and time...

That sounds remarkably like Barbour's Platonia, or the infinite cosmos.
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Offline dlorde

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Re: Please Clarify Quantum Entanglement?
« Reply #24 on: 25/05/2013 23:39:57 »
Quote from: Bill S on 25/05/2013 22:58:14
Quote from: CPT ArkAngel
The entire universe is a superposition of states that we perceive through interactions in space and time...

That sounds remarkably like Barbour's Platonia, or the infinite cosmos.
Yes; the idea has been around since Parminedes, but leaves unresolved the question of why, in a vastly superposed Parminidean block universe, we should have the perception of our awareness moving along the 'time' axis the way it appears to do.
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Offline dlorde

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Re: Please Clarify Quantum Entanglement?
« Reply #25 on: 25/05/2013 23:44:04 »
Quote from: CPT ArkAngel on 25/05/2013 18:08:53
I don't understand how people can follow a path that leads to nowhere...
Perhaps they can't see into the future.

Quote
Refusing to follow other paths is giving up the search for a deeper truth...
Other paths such as?

Quote
One day, not so far, you will all change your mind...
Happens all the time. What deeper truth did you have in mind?
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Offline Bill S

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Re: Please Clarify Quantum Entanglement?
« Reply #26 on: 26/05/2013 00:54:13 »
Quote
......leaves unresolved the question of why, in a vastly superposed Parminidean block universe, we should have the perception of our awareness moving along the 'time' axis the way it appears to do.

"Why" questions tend to be a bit philosophical.  Why is our perception of time and space such that we are unable to experience the realities of relativity in our daily lives?  Why do we exist on a scale that places the processes of QM outside the range of our observations?  Why are we even here?

Perhaps the question should be: If we exist in an infinite cosmos/universe, how would we be able to experience change?
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Offline CPT ArkAngel

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Re: Please Clarify Quantum Entanglement?
« Reply #27 on: 26/05/2013 02:01:45 »
I will tell you only the things i'm sure about.

1. All elementary particles of the universe are entangled. Entanglement is quantized. The level of entanglement is quantized and it decreases as you look further down the chain, starting from the observed particle.

2. The strong nuclear force is gravity at the Planck length.

3. Photons are 2 dimensional particles. There is no space for photons in their velocity direction; this is why there is the spin entanglement (photons are all connected through their spacetime history; their paths). A photon has a longitudinal inertial mass and a transverse gravitational mass. The photon is composed of two oscillating charges, one negative and one positive, the value of each charge is unknown but probably 1 or 1/2. You can't measure the charge because the photon is flat...

4. Everything is made out of photons. Elementary particles are made of two halves of photons. Particles are rotating at the speed of light. The spin entanglement produces the spherical probability function.

5. You can't go faster than light because you are made of light.

6. The Planck length is the minimum length and it represents the maximum density of matter. There is no black holes but there is black rings.

7. De Broglie-Bohm interpretation is good but without signals going backward in time. There is an instantaneity across the universe within the Planck Time. The universe is causal within itself. There is no need for a multiverse.

see this:

There is 2 things to retain from this presentation; the proof of causal paths and the relational model of particles.

See my theory for further explanations in the Theory section.

If you want to discuss about it, start a post in the new theory and i will discuss it with you.
« Last Edit: 26/05/2013 02:07:57 by CPT ArkAngel »
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Offline dlorde

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Re: Please Clarify Quantum Entanglement?
« Reply #28 on: 26/05/2013 16:40:26 »
Quote from: Bill S on 26/05/2013 00:54:13
"Why" questions tend to be a bit philosophical.
True; although there is a certain amount of overlap between 'why?' and 'how is it that...?'

Quote
Why is our perception of time and space such that we are unable to experience the realities of relativity in our daily lives?
That's mainly a question of spatial and temporal scale.

Quote
Why do we exist on a scale that places the processes of QM outside the range of our observations?
Because QM is typically distinguishable at the scale of atoms & molecules, it takes billions of atoms and molecules to make a biological organism, and QM effects are averaged out and lost in the 'noise' of all that chemistry.

Quote
Why are we even here?
Everybody's got to be somewhere ;-)

Quote
Perhaps the question should be: If we exist in an infinite cosmos/universe, how would we be able to experience change?
I don't understand what you mean.
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Offline yor_on

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Re: Please Clarify Quantum Entanglement?
« Reply #29 on: 27/05/2013 01:04:13 »
When I think of it I naively think of it as a ideal 'system', the answer to all quantum mechanical dreams :)
If we define a 'system' as something always giving us a equivalent answer, no matter its spatial and temporal separation. Equivalent instead of 'same' as we can't know the that first 'name', but as soon as we find what it is we must know the other. And personally I don't think there are any hidden parameters to it, if we don't define the way quantum logic works, as being it? Because I don't find quantum logic and the reality we describe macroscopically to be the same, although you can create theoretical bridges as decoherence. And it has to do with scaling something.
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Offline yor_on

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Re: Please Clarify Quantum Entanglement?
« Reply #30 on: 27/05/2013 01:17:21 »
This one is rather educational when it comes to decoherence, and understandable.
http://plato.stanford.edu/entries/qm-decoherence/

This also reminds me of Cherry's comment, although here we see a question arise.

"The measurement problem, in a nutshell, runs as follows. Quantum mechanical systems are described by wave-like mathematical objects (vectors) of which sums (superpositions) can be formed (see the entry on quantum mechanics). Time evolution (the Schrödinger equation) preserves such sums. Thus, if a quantum mechanical system (say, an electron) is described by a superposition of two given states, say, spin in x-direction equal +1/2 and spin in x-direction equal -1/2, and we let it interact with a measuring apparatus that couples to these states, the final quantum state of the composite will be a sum of two components, one in which the apparatus has coupled to (has registered) x-spin = +1/2, and one in which the apparatus has coupled to (has registered) x-spin = -1/2. The problem is that, while we may accept the idea of microscopic systems being described by such sums, the meaning of such a sum for the (composite of electron and) apparatus is not immediately obvious.

Now, what happens if we include decoherence in the description? Decoherence tells us, among other things, that plenty of interactions are taking place all the time in which differently localised states of macroscopic systems couple to different states of their environment. In particular, the differently localised states of the macroscopic system could be the states of the pointer of the apparatus registering the different x-spin values of the electron. By the same argument as above, the composite of electron, apparatus and environment will be a sum of (i) a state corresponding to the environment coupling to the apparatus coupling in turn to the value +1/2 for the spin, and of (ii) a state corresponding to the environment coupling to the apparatus coupling in turn to the value -1/2 for the spin. Again, the meaning of such a sum for the composite system is not obvious.

We are left with the following choice whether or not we include decoherence: either the composite system is not described by such a sum, because the Schrödinger equation actually breaks down and needs to be modified, or it is described by such a sum, but then we need to understand what that means, and this requires giving an appropriate interpretation of quantum mechanics. Thus, decoherence as such does not provide a solution to the measurement problem, at least not unless it is combined with an appropriate interpretation of the theory (whether this be one that attempts to solve the measurement problem, such as Bohm, Everett or GRW; or one that attempts to dissolve it, such as various versions of the Copenhagen interpretation). Some of the main workers in the field such as Zeh (2000) and (perhaps) Zurek (1998) suggest that decoherence is most naturally understood in terms of Everett-like interpretations (see below Section 3.3, and the entries on Everett's relative-state interpretation and on the many-worlds interpretation)."
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Offline yor_on

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Re: Please Clarify Quantum Entanglement?
« Reply #31 on: 27/05/2013 01:26:31 »
That one has a direct relevance to me discussing measuring a time reversal. How would one define such a experiment measuring it locally, using a local clock and ruler? It's logically inconsistent to me. Whatever change I define, will 'move' relative that local clock I use, and that clock does not go backward.
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Offline Bill S

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Re: Please Clarify Quantum Entanglement?
« Reply #32 on: 28/05/2013 19:04:42 »
Quote from: dlorde
Quote
Perhaps the question should be: If we exist in an infinite cosmos/universe, how would we be able to experience change?

I don't understand what you mean.


Probably not a good thing to become embroiled in the infinity stuff in this thread as well.  I would be quite happy to take the question  to " What is your interpretation of quantum mechanics?"
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Offline dlorde

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Re: Please Clarify Quantum Entanglement?
« Reply #33 on: 28/05/2013 19:51:36 »
Quote from: Bill S on 28/05/2013 19:04:42
Probably not a good thing to become embroiled in the infinity stuff in this thread as well.  I would be quite happy to take the question  to " What is your interpretation of quantum mechanics?"

OK, go for it :)
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