Originally posted by AThousandYoung
Right. The reason this isn't in conflict with relativity is that no information can be transferred via this instantaneous communication, I believe.

I am dying for the day when someone breaks that edict! Somebody finds a loophole in quantum theory that busts the whole thing wide open! Just a dream for sure, but it could happen. I am also waiting for confirmation of the spinning superconductor experiment, you know, the one that seems to alter gravity in its vacinity?

Originally posted by AThousandYoung
Right. The reason this isn't in conflict with relativity is that no information can be transferred via this instantaneous communication, I believe.

What does that mean? Did you read the experiments that led to Bell's Theorem? Saying "no information was transferred" seems meaningless and counter-intuitive.

Originally posted by no1marauder
What does that mean? Did you read the experiments that led to Bell's Theorem? Saying "no information was transferred" seems meaningless and counter-intuitive.

As far as I can see it all seems meaningless No1.

If I chuck a stone at you, it's gonna hurt.
If I'm shagging my girlfriend, it's gonna be good.
If I'm watching another US led invasion, it's gonna be counter productive.

If no information, no intelligence, no willpower is involved...what the hell is the point? What does it mean? What is the significance?

Originally posted by no1marauder
What does that mean? Did you read the experiments that led to Bell's Theorem? Saying "no information was transferred" seems meaningless and counter-intuitive.

Appendix I of your source (from the reincarnation thread) shows that no information can be transferred.
http://www.ncsu.edu/felder-public/kenny/papers/bell.html

Originally posted by SwissGambit
Appendix I of your source (from the reincarnation thread) shows that no information can be transferred.
http://www.ncsu.edu/felder-public/kenny/papers/bell.html

I don't see where it says that at all. It concludes:

If you are like me, you will probably find that this explanation is still unsatisfying. We are saying that the electrons seem to communicate faster than light, but somehow relativity is saved because as a technical matter we can't tell that it happened until later. Nonetheless, satisfying or not, Bell's theorem has been experimentally tested and showed that locality must fail, and at the same time relativity has been repeatedly tested and always worked, so until someone comes up with an explanation which shows more naturally why these two results should both be true, we seem to be stuck with getting off on this technicality.

That hardly shows that "no information is transferred"; in fact the part in bold concedes that information is.

The last paragraph of Appendix III concludes:

Because I find this result so remarkable and incomprehensible, I think it bears repeating. In order to explain the failure of Bell's inequality we had to conclude that one of the measurements (presumably whichever one happened first) affected the state of the other electron. Yet relativity tells us it is a matter of perspective which measurement was the cause and which the effect. Although we can't ever distinguish these two perspectives experimentally, the idea that they should both be valid seems to bring into question some of our most fundamental views about causality. Issues such as these which arise in trying to reconcile relativity and quantum mechanics are, in my opinion, among the most fascinating aspects of physics.

Originally posted by no1marauder
What does that mean? Did you read the experiments that led to Bell's Theorem? Saying "no information was transferred" seems meaningless and counter-intuitive.

I have not studied this topic in any great detail. The idea as I understand it is that one cannot, for example, use quantum entanglement to send a message faster than light because the guy on the other end won't know if you checked your particle before he did unless he asks you by some other method which is limited by the speed of light. That is, it is completely impossible to tell anything about a particle by checking it's entangled partner particle's spin except that the other one, if it's checked, will give the opposite result. There's no way to use this to communicate though because you can't tell if the other particle was checked first and you can't pick which spin your particle will have.

There is a strange connection between particles which instantaneously informs the undisturbed particle of the type of measurement just carried out on its partner (however Special Relativity is not violated because no information can be transmitted using this method).

http://www.ipod.org.uk/reality/reality_entangled.asp

However I am not very familiar with this aspect of physics.

Originally posted by AThousandYoung
I have not studied this topic in any great detail. The idea as I understand it is that one cannot, for example, use quantum entanglement to send a message faster than light because the guy on the other end won't know if you checked your particle before he did unless he asks you by some other method which is limited by the speed of light. That is, it i ...[text shortened]... y/reality_entangled.asp[/i]

However I am not very familiar with this aspect of physics.

I see; the claim is that nothing travelled faster than the speed of light - that in some way the action of the separated particles is preordained in some manner. I'm not sure that interpretation is consistent with the results or not.

Here's an article from last month's New Scientist with the interesting title "Reality is an Illusion: Why we are Blind to Quantum Truth". http://www.ipod.org.uk/reality/reality_forever_quantum.asp

It discusses recent research regarding the boundary between the quantum and classical worlds which some researchers now claim doesn't exist.

Originally posted by no1marauder
I don't see where it says that at all. It concludes:

If you are like me, you will probably find that this explanation is still unsatisfying. [b]We are saying that the electrons seem to communicate faster than light, but somehow relativity is saved because as a technical matter we can't tell that it happened until later. Nonetheless, satis and quantum mechanics are, in my opinion, among the most fascinating aspects of physics.[/b]

From the first paragraph of Appendix I:

"Before abandoning relativity, however, we should look a little more closely at what it means to "communicate." This problem will only arise if somehow I can send a message to someone faster than light."

The example of trying to send a hot stock tip to Mary shows that despite the "connection" between the paired electrons, no actual information can be sent. So there is communication (perhaps this is not the best choice of word!) in a sense of the measurement of one electron affecting the state of the other, but not in the sense of actually sending information (Mary can't find out the stock tip until some other form of sub-luminal communication is used).

Edit: I do agree with the author that 'this explanation is still unsatisfying'.

Originally posted by shavixmir
As far as I can see it all seems meaningless No1.

If I chuck a stone at you, it's gonna hurt.
If I'm shagging my girlfriend, it's gonna be good.
If I'm watching another US led invasion, it's gonna be counter productive.

If no information, no intelligence, no willpower is involved...what the hell is the point? What does it mean? What is the significance?

rec'd

Originally posted by SwissGambit
From the first paragraph of Appendix I:

"Before abandoning relativity, however, we should look a little more closely at what it means to "communicate." This problem will only arise if somehow I can send a message to someone faster than light."

The example of trying to send a hot stock tip to Mary shows that despite the "connection" between t ...[text shortened]... ed).

Edit: I do agree with the author that 'this explanation is still unsatisfying'.

How exactly do you propose that the one electron "affects" the state of the other without sending it information?

Originally posted by no1marauder
How exactly do you propose that the one electron "affects" the state of the other without sending it information?

In some theories, the explanation lies in the idea that we are projections of higher dimensions on a dimensional palette. So in that world, two entangled electrons are on the same plane dimensionally speaking and are never separated, even though to us is looks like it.
A way of visualising this is to think of two dots on top of one another, if they move left and right, they look separated, but if they move in and out, the one in back never separates from our pov.

Originally posted by sonhouse
In some theories, the explanation lies in the idea that we are projections of higher dimensions on a dimensional palette. So in that world, two entangled electrons are on the same plane dimensionally speaking and are never separated, even though to us is looks like it.
A way of visualising this is to think of two dots on top of one another, if they move le ...[text shortened]... they look separated, but if they move in and out, the one in back never separates from our pov.

Adding in extra dimensions always seems like a "magic" way out of these type of difficulties. Might as well say "Goddunnit".

Originally posted by no1marauder
Adding in extra dimensions always seems like a "magic" way out of these type of difficulties. Might as well say "Goddunnit".

Here's a Wikipedia article on the topic I brought up earlier:

http://en.wikipedia.org/wiki/No_communication_theorem

I know you don't like Wikipedia, but it cites it's sources so you can look those up if you really want to.

Originally posted by no1marauder
How exactly do you propose that the one electron "affects" the state of the other without sending it information?

That's a tough question. The only way out of it I can see is sonhouse's suggestion that the electrons are not as separate as they appear to be.

I agree that this seems like a "magic" explanation, but so does the idea of instant communication between two electrons millions of miles apart. I'll certainly be watching for interesting discoveries in this field from now on.

Originally posted by no1marauder
Adding in extra dimensions always seems like a "magic" way out of these type of difficulties. Might as well say "Goddunnit".

Well String Theory and its bretheren posit's 10 or 11 dimension. That's in the same catatory I guess. The problem then becomes, can you find evidence for other dimensions? One such effort is analyzing the force of gravity, vis a vis, the famous 1/R^2 relation. Inverse proportionality, so if two masses are at 1 unit apart and the attraction is 1 when they go to 1/2 unit apart, the attractive force is 2, 1/3 units apart, the force goes to 9X, 1/4 units, force goes to 16X, etc. Theory goes if there are extra dimensions, the value of the actual force will deviate from the numbers I gave here, when reaching some minimum distance. Right now, experimentalists have verified Newtonian gravity to within about 50 microns so far and it gets harder to get accurate numbers below that but the experimental guys are hard at work on the problem. They think they will find deviations when they get to 10 microns separation or so. You can see the difficulty involved, you get that close and rival forces have to be factored out, like the casimir force which is an attractive force that mimics gravity at close distances because there is a background of virtual particles flashing in and out of existance faster than any clock or imaging system can detect but it is a real force and when two bodies get very close, the amount of virtual particles on the outside of the body and the ones on the inside show a differance, less virtual particles forming in the gap so it is like an air pressure forcing the two bodies together. This force has been verified many times and has to be taken into account because it would interfere with a gravitational attraction figure. Likewise with electric and magnetic forces, they have to be neutralized perfectly or some partial force would also interfere with the gravity measurement. Tough problem but the experimentalists are a tricky bunch.