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Entangled Particles Break Classical Law of Thermodynamics, Say Physicists

Posted by Soulskill on from the not-in-homer's-house dept.

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.'"

5 of 222 comments (clear)

  1. Would not one have to spend energy... by PaulBu · · Score: 5, Insightful

    ... beforehand to entangle particles? And then put one from each pair into separate boxes?

    Something tells me that energy conservation still holds...

    Paul B.

    1. Re:Would not one have to spend energy... by __aaltlg1547 · · Score: 4, Insightful

      Yep. Something was not included in the math. Also missing: a plausible means of entangling a boxfull of particles and a plausible means of using the entanglement to harvest energy. But aside from the mathematical sleight of hand and the unphysicality, everything looks legit.

    2. Re:Would not one have to spend energy... by Anthony+Mouse · · Score: 4, Insightful

      According to TFA, the particles are already in an entangled state.

      That seems very "Hydrogen Economy." You can get energy from Hydrogen, but only if you "somehow" already have Hydrogen. Where do we get a continuing supply of entangled particles without expending energy?

  2. Any cost to entangled particles ? by Taco+Cowboy · · Score: 4, Insightful

    TFA talks about "Entangled Particles" breaking the law of thermodynamics, seemingly getting something out of nothing

    I am not good at all on particle physics, but I believe that particles in their ordinary state do not come "entangled", right?

    So, in order to get particles that are already in the "entangled" state, something must have happened to ordinary particles, first, right?

    If so, what's the cost (in term of energy) to get originally un-entangled particles to be "entangled"?
     

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    1. Re:Any cost to entangled particles ? by Anonymous Coward · · Score: 2, Insightful

      You're forgetting an important variable: time. Assuming we have a source of entangled particles and a functioning gate between the two 'boxes' it may be possible to extract energy from the system. That's all they are saying.