Physicists Smash Record For Wave-Particle Duality 95
KentuckyFC writes "One of the central concepts in quantum theory is wave-particle duality — that every object can be thought of as a particle and a wave. Indeed every object has a quantum wavelength associated with it and so can form a quantum superposition with itself. That's easy to demonstrate with fundamental particles such as photons and electrons by passing a beam of them through a double slit and watching the interference pattern that forms on the other side. In this way, physicists have observed the interference patterns associated with atoms and even molecules such as buckyballs. Now, a group at the University of Vienna has observed the interference pattern formed by the quantum superposition of molecules containing over 800 atoms, or around 5,000 protons, 5,000 neutrons and 5,000 electrons. That's the most macroscopic occurrence of wave-particle duality ever observed, they say."
Whatever (Score:4, Funny)
Wake me up when they can find the wavelength of a Turtle, because quantum theory holds that the universe is made of picoturtles. Why should anyone believe quantum "science"?
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Picoturtles? What about the femtoturtles? It's turtles all the way down!
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don't forget ninjaturtles.
Re:Whatever (Score:5, Funny)
Don't forget the four elephants on the back of the turtle holding the world up. It's like you people had never taken a science class before.
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Octarine
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Dude, that's a COLOR, not a gender!!!!
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Again, you display your gross ignorance of basic science!
Colors *are* genders.
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Why should anyone believe quantum "science"?
For starters, no picoturtles.
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Picoturtles or it didn't happen.
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This [telegraph.co.uk] close enough?
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Maybe because the science works. So you should start learning to eat turtle, beginning with your own words..
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The equation is irrelevant. The Chelonian Uncertainty Principle demonstrates that the more accurately you know the momentum of a turtle, the less accurately you know its position. Since any usefully accurate value for its quantum wavelength would need very high accuracy for its momentum, you would never be able to find the turtle for which you had made your calculations, especially since they can look just like little rocks under the water and are naturally given to hiding.
The Turtle Moves!
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but it is turtles all the way down, so like electrons, we really only observe a turtle-shaped hole in the sea of turtles
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no, you are confused. this is not the size of an object, but uncertainty in position. for a turtle at normal velocities, and for your body, that "de Broglie" wavelength is quite small
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Almost. It's a Quantum Logo program. Where you have commands like
Not enough (Score:5, Funny)
I won't be happy until they get a whole cat [wikipedia.org] to exist in superposition.
Then a lab assistant [wikipedia.org].
THEN THE WORLD!
Re:Not enough (Score:5, Funny)
There are lots of pictures of coherent cats on the internet. Unfortunately as soon as somebody looks at them, they immediately collapse into a picture of a lolcat.
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Looks like we're going to need another Timmy!
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useless (Score:2)
Re:useless (Score:4, Funny)
Finally they can stop scratching at doors until you let them through. Best invention ever!
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good grief, what use is a teleporter just for cats?!!
Imagine: It's 3am on a Wednesday night. You are up on the Internet arguing with a troll.
Suddenly you press a large jolly and candy like button on your cat teleporter, and without warning a thousand terrified cats materialize directly above the troll and rain down upon him like the clawing and hissing metric ton of fur it is.
<Nathan Explosion> Release The Kitties!
My evil twin (Score:2)
Wait. I'm the evil one. Never mind.
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What about politicians? Thats and entire person who can take dual positions and only pick a single position based on the audience.
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Have you ever seen a politician that is coherent?
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THEN THE WORLD!
Greg Egan did it.
Can you do this in reverse? (Score:1)
I mean, their current setup is displaying an interference pattern.
But how about doing it in reverse. Start from existing interference pattern, and go through all possible molecules until you find the one which matches the same interference pattern?
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I was thinking more like getting teleportation working. if we know the interference pattern, can we use that info to construct the molecule?
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I'm pretty sure the interference pattern is determined by the mass and velocity of the particle. Because of this the pattern would not be unique to any one particle.
Vortices in Superfluids beats this (Score:1)
Vortices in superfluids 3He or 4He are an expression of the wave-function.
Experiments have been done up to 70 Mol, that is a lot more that 800 atoms.
Re:Vortices in Superfluids beats this (Score:4, Interesting)
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Re:Nothing new (Score:5, Informative)
No. They observed what we already expected. Our currently best theories predicted it. But then, our then-best theories didn't predict the null result of the Michelson-Moreley experiment, or the photoelectric effect. We don't really know it until we tried.
Note that there are theories which postulate a modification of quantum mechanics for sufficiently large objects as solution to the measurement problem. Therefore measurements like this can indeed differentiate between competing theories. Although I think you'd need to test even larger objects to test those theories.
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I feel this is a rather underestimated aspect of deductive logic that all science is based on, nobody knows that the "laws" of nature that we know them are universally valid. Even if you're doing a high school experiment it is "new" science, maybe things are different today than they were yesterday. You don't expect them to be, but in theory they might be. Every step of the way from confirming gravity for atoms to gravity for galaxies is valuable, expanding the experimental proof of an apparently correct fo
So (Score:2)
What does this mean?
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It means that people can be amazed by just about anything.
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.
The mathematics is merely a statistical description of the observations, not details on the mechanism for the underlying process. Please wake me when they describe the actual underlying process.
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It's the political holy grail! They will be able to vote yes and no at the same time.
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It's the political holy grail! They will be able to vote yes and no at the same time.
Politicians are already in a superposition of their principles - the measurement of what those principles are depends entirely on the who the observer is doing the measuring.
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Re: So (Score:2)
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The mathematics is merely a statistical description of the observations, not details on the mechanism for the underlying process. Please wake me when they describe the actual underlying process.
Um, no. Ever hear of Bell's inequality?
Re: So (Score:2)
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This is an argument I've had in the past.
If taken a little further, it leads to the question: will science ever end?
At one point, we just knew that matter was made out of small things we called atoms.
We asked what are atoms made of, and we learned they are made of protons, neutrons, and electrons.
We ask what are protons and neutrons made of, and we found quarks.
What are quarks made of? I don't know, because I'm not a physicist. Maybe someone else can answer that for me.
But what are electrons made of? Sci
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Currently, quarks are assumed to be elementary particles, just like electrons.
Actually no. Experiments have not shown any evidence for them not to be elementary. However, it is impossible to conclusively show that they are elementary. After all, they might have a substructure which onl
Pics (Score:2)
Pics or it did or didn't happen.
Oblig. SMBC (Score:1)
Particle, wave, Nobel prizes...a family affair (Score:5, Interesting)
love this one:
"In 1906, J.J. Thompson had received the Nobel Prize for proving that electrons are particles;
in 1937 he saw his son awarded the Nobel Prize for proving that electrons are waves.
Both father and son were correct, and both awards were fully merited."
http://en.wikipedia.org/wiki/J._J._Thomson [wikipedia.org]
http://en.wikipedia.org/wiki/George_Paget_Thomson [wikipedia.org]
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yes most marriages until recently were single slit experiments, but now we allow double-slit marriages
Chickens. (Score:2)
Physicists have evidence of the Wave-Particle Duality of Macroscopic Chickens in Minecraft. [youtube.com]
Wave-particle duality is not the interesting bit (Score:2)
But quantum decoherence is, i.e. how the wave nature is actually suppressed in our macroscopic world.
QM offers up the Ehrenfest theorem to explain how we get there, but this theorem is not completely consistent [wavewatching.net]. So gaining an experimental leg up on this process, that the Copenhagen Interpretation just swept under the rug as 'Quantum State Collapse', is what makes experiments with ever larger quantum systems so interesting.
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Sounds to me like decoherence. Which certainly explains why the interference disappears, but does not explain why we see a single, definite result. That is, it explains why the stripes in the double-slit experiment vanish, but it doesn't tell us why we get dots.
Anyway, you don't need to have a macroscopic object to destroy interference. Already entanglement with another microscopic object is sufficient to make interference effects disappear. All which macroscopic objects add is that decoherence becomes prac
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Indeed, the understanding of decoherence has fortunately made great strides since Bohr and Heisenberg coined the Copenhagen Interpretation, and we have a much better understanding of how the interference 'dissipates'.
You are exactly putting the focus on the remaining most intriguing puzzle, why do we experience a single reality? I.e. only see one moon, as Einstein put it. To me it seems there's a deep link between decoherence and entropy lurking in there, something, that despite all the QIS progress, we st