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Offline JP

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Is remote entanglement not proven ?
« Reply #50 on: 25/04/2011 18:19:38 »
JP: we might be on the same page now.
Your statement that, "The rules to then propagate to distant observers are entirely deterministic.", reads like something I might write.

Under that interpretation; would it be correct to state that a measurement of a particle by one distant observer would not affect the other particle or the other distant observers results.
It depends somewhat on your interpretation of quantum mechanical measurements.  If you work with something along the lines of the Copenhagen interpretation, then measurement collapses the wave function,  which happens simultaneously for both particles.  So one measurement will have an effect on the other measurement.  This is something Coleman also doesn't like.  If you write the observers as a quantum system as well, then there is no collapse and the observers are now entangled in a quantum state with the particles.  This is the kind of idea Coleman is arguing for.  You no longer have to assume that collapse of the wavefunction caused by one observer affects the other observer, but you do have to allow observers to be quantum systems. 

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Would it also be correct that there is no single, composite non-locality incorporating both particles as they propagate to distant observers.
I'm not sure what you mean by this. 
 

Offline yor_on

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Is remote entanglement not proven ?
« Reply #51 on: 25/04/2011 18:52:55 »
In what way is there no Wave collapse JP? If I assume the observer to be a quantum system then I can't expect any observation either, can I? And in that case there will be no definition of a outcome either. You might want to argue that everything happens even when we are dead :) But how can you prove it?

There has to be a observer for the tree to fall, or to have fallen, that doesn't matter actually. You can as easily define it as for being a change someone has to observe it. Or is it in some other matter of way he means? Haven't listened to him as it craved the latest update of flash, and I don't really trust flash that much. But now it seems that I have no choice. Why does a university filled with learning use one of the most insecure protocol's there is, namely flash, and demand it to be the latest version?

Check up the discussions on the security for it. Some security experts refuse to use it at all, but I used v.8 to now, as it has some really sweet third party applications. Ah well, hopefully it will stay away from my private areas, as the girl told the boy :)

ahem..

 

Offline JP

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Is remote entanglement not proven ?
« Reply #52 on: 25/04/2011 21:05:50 »
It depends how you define observation, yor_on. 

If you're in the Copenhagen interpretation, then a wave function collapse forces the quantum particle to choose a state.  This seems nonlocal, since the pare of the wave function at observer 2 is affected by this choice of state based on a measurement by observer 1.

If you're in the many worlds intepretation, then what you observe as a result of the measurement determines which universe you're in.  In the other branch of the measurement corresponds to another you in another universe.  You could argue that nothing nonlocal is occurring, since both universes are purely local.  You've just confined yourself to one of them in which the other observer agrees with you. 

This is why there are so many possible interpretations here, and it's hard to say one is wrong.  Coleman's point of view is interesting, but it's impossible to say if he's right, since other interpretations of the mathematics exist and predict the same experimental results.
 

Offline yor_on

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Is remote entanglement not proven ?
« Reply #53 on: 26/04/2011 00:42:56 »
Ah but when you think that way you are treating it macroscopically, don't you :) A 'human' 'observing' quantum system and so get the best of two worlds :)

Not fair me man, QM is not a human, and macroscopic phenomena is not QM. How the he* can anyone define a 'whole' human Quantum mechanically? How many particles interacting is that, and what says that they have a coherence as from that minuscule view. Time doesn't? As far as I understands it. and there is all those interactions coming from us, creating those new 'worlds', that in their turn 'instantly' start to 'interact' and create 'new worlds', than in their turn 'instantly' .. , etc, into absurdity :)

I don't trust that one at all. Too much improbability for me.
==

You see, to me its not only taking every probable path, but somehow then, with every new 'world' created by every 'new world' there will become more probabilities. Either that or we will have to assume that somewhere the 'universe' has to repeat itself, in infinity. :) Mirrors inside mirrors inside mirrors inside ...
==

But if I allow it to be modifiable into something in where only one path materialize then we have something that do a even more thorough work than 'Sum over paths' :) as it actually fills the 'void' with everything, a little like those Quantum computers choosing the 'best' possible path. Or maybe the easiest :)
==

Furthermore it seems to build on the assumption that everything can, and will, be created 'instantly' from nothing at all, and also doing so in greater and greater 'amounts/chunks' of universa? Infinity around the corner with free 'energy' as your best friend that is, just tell us if you want to 'interact' Sir :)

Naaah.

ahem :)
« Last Edit: 26/04/2011 01:05:26 by yor_on »
 

Offline JP

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Is remote entanglement not proven ?
« Reply #54 on: 26/04/2011 03:39:54 »
Figuring out how macroscopic objects and classical mechanics fit into the overall QM picture is a big question, though not really an important one.  What I mean by that is that we can do the math and get results without having to worry too much about it.  But these are fundamental questions for QM: what is an observer, when does something go from quantum mechanical to classical mechanical and what happens when a QM system interacts with a classical system?

Coleman's view, which is what Sciconoclast was bringing up, is that classical mechanics is just an approximation to the true quantum mechanics that describes the universe.  I think he's saying that the real question to ask is what makes QM look like what we call classical mechanics.  Having classical observers collapsing wave functions isn't a useful interpretation in his view.  Having quantum observers interacting with quantum wave functions is proper, and in some cases it will reduce to classical observers.

I actually tend to agree with Coleman.  I think the trick is decoherence, though I admit that's just one interpretation of things.   

I think we're dragging things a bit off track, though.  If you want to go into it further, perhaps we can start up a new thread about the quantum/classical boundary?
 

Offline yor_on

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Is remote entanglement not proven ?
« Reply #55 on: 27/04/2011 03:07:35 »
Yes JP, looking at it that way it becomes different, as long as we ignore the macroscopic definitions as they, in a way, becomes meaningless for the 'quantum reality'. And I'm not joking there, is it so for me too. If I choose to look at it from that minuscule plane where neither times arrow, nor 'solid matter' exist, everything 'dissolves' into one thing. And that 'thing' does not use our delimitations. So I can see what you mean, hopefully :)

From that point of view the question, as you say, becomes what creates those delimitations, forces, and 'fields'. But whatever reality you look at it from, both set of definitions exist, and macroscopically 'many worlds' becomes just to 'messy' for me. I would rather see a universe, more or less 'static' in appearance, begetting all we know from time and macroscopically our own 'arrow of time'. In a way making us into a dream, dreamed by the arrow of time..

Heh :)
 

Offline yor_on

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Is remote entanglement not proven ?
« Reply #56 on: 27/04/2011 03:50:34 »
And yes, the idea of decoherence have similarities with my thoughts of what 'distance' is, something contracting and magnifying, giving us different presentations of 'SpaceTime'. It makes sense JP.

"When two systems (and the environment would be a system) start to interact, though, their associated state vectors are no longer constrained to the subspaces. Instead the combined state vector time-evolves a path through the "larger volume", whose dimensionality is the sum of the dimensions of the two subspaces. A square (2-d surface) extended by just one dimension (a line) forms a cube. The cube has a greater volume, in some sense, than its component square and line axes. The extent two vectors interfere with each other is a measure of how "close" they are to each other (formally, their overlap or Hilbert space scalar product together) in the phase space. When a system couples to an external environment, the dimensionality of, and hence "volume" available to, the joint state vector increases enormously. Each environmental degree of freedom contributes an extra dimension."

I actually think I like this interpretation. It's very much a question of how to see 'dimensions' to me. I don't really like the definitions we use thinking of them as 'singular' though. But the concept of the 'sum' becoming more than its parts seems possible to me. After all, the Bekenstein bound and Lorentz contraction states something similar although in the 'opposite' direction as I see it. Your 'space' is a fluid thing. But to me there should be 'wholeness' to what we call 'dimensions' That is, we might manipulate 'SpaceTimes' properties (dimensions) as 'singular' theoretically, but I don't expect them to be so practically myself.
 

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Is remote entanglement not proven ?
« Reply #56 on: 27/04/2011 03:50:34 »

 

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