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I know this probably isn't exactly a truely scientfic message board, but it since this idea related to a real life ansible (at least in function, if not design) it seemed like a good place to voice it.
There is a concept in physics right now called entangled pairs, or cubits (seen q-bits too) wherein you have two related subatomic particles. When you influence one, the other reacts instantly no matter how far away it is.
Just search for entangled pairs on google, youll get plenty of hits.
Most media attention has focused on the possibility of applying this towards ultra-fast computers, but if I understand the concept right I thought of another application for it.
If the effect is instantaneus no matter the distance between the two particles, does that not equal faster than light communications?
I know there were issues about mass producing enough of these little guys to do any sort of mass production, but does this make sense? Say a Manned mars mission 20 years from now, perhaps there will not be any time delay for communication.
Posts: 375 | Registered: Mar 2005
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I am 100% that the people who spend their lives obsessing about these things have not thought of that possibility.
Posts: 3564 | Registered: Sep 2001
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I had always assumed that this physical phenomenon was what Card based his ansible on. In other words, I thought the fictional device was conceived because it already was recognized as a theoretical possibility in the real world.
Could be wrong, though.
Posts: 6394 | Registered: Dec 1999
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"Most media attention has focused on the possibility of applying this towards ultra-fast computers, but if I understand the concept right I thought of another application for it."
You're pretty late with that theory. Heck, even Card's hypothetical ansible operated on an (imaginary) mechanism for that behavior, which he called philotic twining. I'd be surprised if Einstein himself hadn't commented on the possibility.
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Oh, im sure it has been thought of. Course, the philotic twining of cards was purely fictional. It was based on connections between a persons social networks.
Great idea for books, but its not sound fundemental physics.
Dont need to flame me on this, I don't think im the only one on the planet to come up with this idea, I just want to know if it is a feasible, testable application of a known phenomina.
Posts: 375 | Registered: Mar 2005
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The problem is that while it sounds cool in application, it's actually of limited utility in practice because all quantum principles still apply. Here's an explanation from a physicist:
quote:The key to resolving the "paradox" is that even though the electrons are widely separated, they must be still treated as a single quantum system due to their entanglement. In a sense, all the information needed by both electrons is already contained in the system (though the measurement result is NOT predetermined - there are no "hidden variables"). It seems that this type of faster-than-light "communication" is permitted by relativity since it cannot lead to causality violations. The important feature of such communication as far as relativity is concerned is that it would be impossible to send a message using the process.
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I had an Aunt Sybil and she knew nothing about physics, and I doubt any physicist knew anything about her, except for that one creepy professor in the odd glasses who used to go out with her on Einstien's birthday but I don't think that's what they meant by entangled pairs or even philotic twining because though she had twins, that was due to my Uncle Clarence who was married to my Aunt Beatrice. You want to talk about Testy. So you could imagine he attempted faster than light movement but Aunt Beatrice caught him anyway and....
Visit the sight now and then, just had this thought earlier, so figured i'd register and voice it here.
Actually, with the thousands upon thousands of topics, i figured it probably would of been beat to death, but was just too lazy to see if it had already been posted.
That quote from Tom Davidson's physicist really kinda answered the question though. I wont pretend I truely understood it, but the gist of it was, "Nope, won't work."
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Basically, TK, manipulating one half of the entangled pair would break the system. And since you'd have to manipulate them to communicate, it's not workable. Posts: 37449 | Registered: May 1999
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Thanks for your confidence, Jay, but I don't really know much about entanglement. I'll try to explain a bit better why it wouldn't work, though.
First, you have to understand what entanglement is. It is essentially a state where, if you know the state (spin, isospin, colour, whatever) of one particle, you know the state of the other. For purposes of this explanation I'll work with spin, which can be up or down.
Now, right away this suggests a classical analogy which you may find useful. Suppose I prepare two envelopes, one with the Queen of Hearts inside, the other with the Queen of Spades. I shuffle the envelopes and send one of them to Jupiter, then open the one I have left. If my envelope has the Queen of Spades inside, I immediately know that the Jupiter envelope has the Queen of Hearts; likewise, if my Jupiter correspondent checks his envelope, he'll know what colour of card I have. But this doesn't give him any useful information, because I do not control which envelope he has. Thus I cannot send him a message in this way. I cannot send him the envelope with the black Queen, and then manipulate the measurement so that I find a black Queen in my own envelope, giving him the red.
Now, quantum states are a bit more complicated, because when I send an electron to Jupiter without measuring its spin state, it doesn't make sense to say that I've sent a spin-down electron and kept a spin-up electron for myself. It's not just that I don't know whether my electron is spin-up; God himself doesn't know, any more than he knows what's north of the North Pole.
Nevertheless, the fundamental problem remains : When I measure my electron's spin, I instantly 'cause' the other electron to take on the other spin - it was this faster-than-light influence that Einstein called 'spooky action-at-a-distance', and disliked. But since there's no way for me to influence what I'm going to measure on my electron, I also cannot influence what my friend on Jupiter is going to see. He will measure spin-up and spin-down with equal probability; it's only when we get together afterwards and compare notes that we'll be able to check that he measured spin-up all the times I was measuring spin-down.
Now, it's true that we don't really understand what goes on when we measure a quantum system and the wave-function collapses. It is by all means possible that we'll find some way of influencing this in the future; if so, however, an ansible will be the least of the inventions to flow from that. Perpetual motion springs to mind : Just make the wave-function collapse in a form with less entropy than it had before. Teleportation : Measure a man's position, and collapse the wavefunction over there instead of over here. Cold fusion : Just teleport one nucleus into the other, avoiding that nasty Coulomb barrier. Magic! Wave your hands in the right way, and all the high-energy atoms converge on one spot - instant fireball! Faster-than-light travel, with all the inherent paradoxes. In short, don't hold your breath waiting.
The use of entanglement to create encryption that is unbreakable even in principle is another matter, but one that I don't really understand myself.
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Heck, even Card's hypothetical ansible operated on an (imaginary) mechanism for that behavior, which he called philotic twining. I'd be surprised if Einstein himself hadn't commented on the possibility.![[Wave]](graemlins/wave.gif)
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