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Entangled Particles Break Classical Law of Thermodynamics, Say Physicists
New submitter Zex_Suik writes "Japanese physicists have used one of Maxwell's thought experiments and the ability to turn information into energy to extract more energy from an entangled system than should be possible according to the laws of thermodynamics (abstract). From the article: 'Imagine two boxes of particles with trap door between them. You want to use the trap door to guide the faster particles into one box and the slower particles into the other. In a classical experiment you would have to measure the particles in both boxes to do this experiment. But things are different if the particles in one box are entangled with the particles in the other. In that case, measurements on the particles in one box give you info about both sets of particles. In essence, you're getting information for nothing. And since you can convert that information into energy, there is clear advantage when entanglement plays a role. That's hugely significant. It means that the laws of thermodynamics depend not only on classical phenomenon and information but on quantum effects too.'"
doesn't seem to match the rest of the article. TFA talks about how they can extract more usable energy from the system using entanglement, but it doesn't violate any physical laws. The only violation is in the title!
Actually that happens all the time. Empty space has energy, and energy and mass are interchangeable. Thus particles pop in and out of existence continuously. http://en.wikipedia.org/wiki/Vacuum_state
*I'm not a physicist, please don't kill me for getting it completely wrong.
This isn't about antiparticles; it's about information being exchangeable for energy.
This is really fascinating in that they've actually implemented Maxwell's Demon. A bit of backstory: Maxwell's Demon is a thought experiment about there being two chambers with a tiny, atom-sized demon sitting guarding an atom-sized gate between them. If there's a high-energy particle coming, he open's the gate. If there's a low-energy particle, he lowers the gate. Hence, you end up doing work (pumping heat) without a relevant source of energy (since there's no realistic constraints on the mass of the demon or the gate, they can be discounted). Entropy is going in the wrong direction. The question is: would such a thing work, violating the laws of physics, and if not, why?
The solution was that to know when to open the gate, the demon would have to measure the incoming particles. And it turns out that the entropy change involved in the measurement is more than the gain from what the demon is doing. But then later a hole in this argument was pointed out: if you have information on quantum states stored in a "memory", the demon doesn't need to measure the particles. But since memory can't be infinite, at some point you must cause the entropy change that the information storage is hiding. Information is basically acting as a form of energy.
Here, from the sound of it, they've actually implemented that in the real world, which I find just fascinating.
The chloride owes the sodium money.
I should have linked to this in the submission, but here is the paper http://arxiv.org/pdf/1207.6872v1.pdf From their abstract: "entangled states require less measurement cost because we can perform feedback control without decreasing the entropy of the system, and hence the memory does not need entropy production to compensate for the feedback gain."
But the flaw is that it takes energy to entangle particles. You simply don't get anything for nothing... ever.
However, whatever the universe is doing, it is doing it forever, because you also cannot destroy energy, only change its form.
Therefore all possible permutations of energy and form, that are logically possible, will eventually occur.
Black can never be white in one universe unless it is defined to be the opposite in the other.
That is, until the next zebra crossing, at which time all bets are off.
Information has no place in physics?! Are from the 1950s or something? You might like to take a look at some papers by Stephen Hawking on the black hole information paradox. Or, perhaps more directly to the point and more accessible, see if you can figure out what the Wikipedia article on "Physical information" is about.
God hasn't even created the world yet, but he will have by the time you finished reading this post.
You aren't even reading it; you'll just falsely remember reading it.
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No mention of hell in the Bible? Informative? Seriously?
But the fearful, and the unbelieving, and the abominable, and murderers, and whoremongers, and sorcerers, and idolaters, and all liars, will have their part in the Lake burning with fire and brimstone, which is the second death.
-Revelations 21:8