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Wina
2009-Jan-20, 09:23 AM
I've been trying to research a phenomenon in quantum physics I once heard about for part of my third novel... Problem is, I'm positive it was something which was proven but I can't figure out how to properly search for it on the web and get the response I'm looking for. I remember something in the study having to do with proving that according to quantum physics, an atom can exist in two places simultaneously and that the relative distance from the locations doesn't actually factor in.

Any tips even on a good search word would be helpful, thanks.

Jens
2009-Jan-20, 09:28 AM
I guess you're looking for "nonlocality" or "action at a distance". Maybe "spooky action at a distance"?

Or "quantum entanglement". That's probably the term you want.

gzhpcu
2009-Jan-20, 09:50 AM
All you wanted to know about quantum entanglement, but were afraid to ask, here:
http://en.wikipedia.org/wiki/Quantum_entanglement

:)

alainprice
2009-Jan-20, 12:54 PM
There's always the little sister, 'quantum tunneling' .

Tensor
2009-Jan-20, 01:32 PM
Two places simultaneously sounds more like superposition (http://en.wikipedia.org/wiki/Quantum_superposition).

Wina
2009-Jan-20, 06:57 PM
Not to sound picky but I looked through all of your suggestions so far and none of them addresses what I was thinking of (though they were all interesting to read up on, thank you). I could swear I had read about a study where some kind of energy was applied to an atom and the atom was observed to exist in more than one place simultaneously as a result. Something kind of similar to the Bose-Einstein Condensate possibly, though I can't be sure. But as I remember it, the data was not "fuzzed up" when observed; it was a crystal clear observation that the atom (the SAME atom) existed in two places simultaneously.

Wina
2009-Jan-20, 06:58 PM
Of course I might just have mis-interpreted what I read the first time. It was a good while ago and my memory on the subject is cloudy...

Tim Thompson
2009-Jan-20, 11:44 PM
But as I remember it, the data was not "fuzzed up" when observed; it was a crystal clear observation that the atom (the SAME atom) existed in two places simultaneously.
In this case your memory is faulty. No such observation has ever been made. But it is reminiscent of a tale in George Gamow's book "Mr. Tomkins in Wonderland", where Planck's constant was close to 1 instead of 10-34, which resulted in multiple copies of everything, but only one of which was real.

alainprice
2009-Jan-21, 12:33 AM
The closest to what you're now suggesting that I can think of relates to quantum computing.

A property of an atom can be in two places at once, but each atom is individual. You create a pair of particles, and they must have opposite spin. You wait until the distance between them is large, and then measure the spin of one particle. The other particle corresponds with opposite spin, but there's really are two different particles. They're just tied together since they were created by the same event.

Quantum teleportation might point you in the direction you seek, since it's really a quantum copier.

Wina
2009-Jan-21, 06:29 AM
interesting how alainprice hits it on the head without any clues. I was trying to get the answer without sounding like a goofball for the question. But now that the cat's out of the bag.... I'm trying to justify a second copy of an object being created at an extreme distance which is perfectly identical at the atomic level. (gotta love the suppositions in sci-fi ey?)

alainprice
2009-Jan-21, 01:39 PM
I've said it before and I'll say it again. I feel a teleporter/copier is possible.

The first problem we have is uncertainty. Star trek had their Heisenberg compensators, I have annihiliation.

If we annihilate particle x, can we not see where it was(the location of the annihilation event) and how fast it was going(total momentum is conserved as well)? Therefore, as long as we destroy the test particle, we can gather all of its information. We can use that information to make copies.

I don't see how nature is trying to prevent this.

Honestly, I don't see a consciousness being copied.

Tensor
2009-Jan-21, 02:34 PM
I've said it before and I'll say it again. I feel a teleporter/copier is possible.

The first problem we have is uncertainty. Star trek had their Heisenberg compensators, I have annihiliation.

If we annihilate particle x, can we not see where it was(the location of the annihilation event) and how fast it was going(total momentum is conserved as well)? Therefore, as long as we destroy the test particle, we can gather all of its information. We can use that information to make copies.

Nope. Position and Momentum are complimentary properties. The better you measure one, the more uncertain the other becomes. This is one of the basic HUP examples. We can't measure the two properties exact enough to make a true copy of that particle.

alainprice
2009-Jan-21, 03:47 PM
I have no intention on measuring the test particle with photons. I plan on annihilating it and then measuring the by-products(which conveniently may already be photons).

If photons are emitted, I can calculate much of what is needed. Admittedly, not everything, but a lot.

Basically, I'd like to reinvent the PET scan into a quantum scan. A man can dream, can't he?

I totally get uncertainty. It's a result of the wavelike nature of particles.

spoerl78
2009-Jan-21, 03:56 PM
The only thing which can be teleported
(right now in theory and experiment) is information,
something like the spin state of a system, for example
electron, protons or photons.
But in this case you don't have to know
the system completly, so non-commuting observations
(like position and momentum, for spins you would measure
polarization of the spin-magnet along the 3 directions in space)
are not necessary.

But the information on the original spin is destroyed during the teleportation
process.

As for Quantum copiers, I think I'm pretty (Yes I am ;-) sure that
they are not possible due to simple quantum mechanical relations.
I'll try to find a good link on that.

swansont
2009-Jan-21, 03:58 PM
I've been trying to research a phenomenon in quantum physics I once heard about for part of my third novel... Problem is, I'm positive it was something which was proven but I can't figure out how to properly search for it on the web and get the response I'm looking for. I remember something in the study having to do with proving that according to quantum physics, an atom can exist in two places simultaneously and that the relative distance from the locations doesn't actually factor in.

Any tips even on a good search word would be helpful, thanks.

This may just have been a discussion of the wave nature of quantum mechanics, and "which path" demonstrations that [show that] classical trajectories do not exist. So in the double-slit experiment, for example, the photon or electron goes through both slits, and some might regard this as being in two places at once.

alainprice
2009-Jan-21, 04:07 PM
The intensity of the diffracted pattern seems to indicate the particle was at both slits, in the double-slit experiment. Not classical at all.

Wina
2009-Jan-22, 06:36 AM
I had, at one point, considered the idea of mapping the atomic structure of the original object, communicating that information to your destination and having a completely new second copy created there (which, I understand, was once the sci-fi focal point of a Heinlein novel). I abandoned using this concept however for several reasons (primarily that it had been used in a Heinlein novel, and secondarily that this would leave the originals in a place that I wouldn't want them to remain and destroying them seemed a bit.... anti-audience friendly).

Ufonaut99
2009-Jan-22, 12:09 PM
I remember something in the study having to do with proving that according to quantum physics, an atom can exist in two places simultaneously and that the relative distance from the locations doesn't actually factor in.

I found this from Scientific American (http://www.sciam.com/article.cfm?id=schroedingers-cation)

The workers then stimulated the atom with a laser just enough to change its wave function; according to the new wave function of the atom, it now had a 50 percent probability of being in a "spin-up" state in its initial position and an equal probability of being in a "spin-down" state in a position as much as 80 nanometers away, a vast distance indeed for the atomic realm. In effect, the atom was in two different places, as well as two different spin states, at the same time--an atomic analog of a cat both living and dead.

Of course, as soon as you observed one, the superposition would collapse.

mugaliens
2009-Jan-22, 06:28 PM
Honestly, I don't see a consciousness being copied.

I do, provided consciousness is inherent in the electrochemical makeup of one's neurons.

But that's a topic for another thread...

Wina
2009-Jan-23, 06:33 AM
I've always held the same belief, Mugs. But then again, living in a ridiculously Catholic household, I'm not allowed to say such things without expecting a five hour debate/screaming at me festival. >)

mugaliens
2009-Jan-24, 05:20 PM
Yuch! Glad you're hanging around here, instead!

Michael Noonan
2009-Jan-25, 04:30 AM
I've been trying to research a phenomenon in quantum physics I once heard about for part of my third novel... Problem is, I'm positive it was something which was proven but I can't figure out how to properly search for it on the web and get the response I'm looking for. I remember something in the study having to do with proving that according to quantum physics, an atom can exist in two places simultaneously and that the relative distance from the locations doesn't actually factor in.

Any tips even on a good search word would be helpful, thanks.

On a relativistic scale an Einstein Ring is a multiple image of the same object which is separate copies of information of the same object. The same object appearing in two places at once. Put that through a curvature of space and one can see the same object in different time frames.

On a quantum level it would appear to require very high powered particle physics or extreme laser power to bend the fabric of space on a micro level. The same object may appear twice and even in slightly different time frames on a Planck time scale but the measurement would indicate the images are extremely close to each other.

As for the ghost in the machine the conscious perception of emerging from a deep anesthetic is a continuance of a lived reality with a remembered past in a good number of cases. Some stories from the recovery room floor from staff who have to put up with the uptake of accessing reality after a gap would be interesting unless it is a medical taboo to talk about.

Wina
2009-Jan-25, 06:51 AM
Well that's the scary part Michael... my overbearing catholic family are ALL nurses >) (who THINK they're doctors.... meanwhile one of them misdiagnosed a tumor for a hernia...)

Sandoval
2009-Jan-29, 05:46 AM
I found this from Scientific American (http://www.sciam.com/article.cfm?id=schroedingers-cation)

Of course, as soon as you observed one, the superposition would collapse.

Thanks RobA, I knew this experiment was the answer to Wina's question, although I had just a faint recollection of having read about it somewhere. This thread, though, seems to have gone haywire:


Well that's the scary part Michael... my overbearing catholic family are ALL nurses >) (who THINK they're doctors.... meanwhile one of them misdiagnosed a tumor for a hernia...)

Wina
2009-Jan-30, 02:54 AM
It seems to me though, that this experiment works on a theoretical sense or, at the least, an extremely microscopic sense. (of course I may be missing the point entirely). But I've been thinking on a universally grander scale. Then again, that's where science fiction comes into play...