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Argonne researchers posit way to locally circumvent Second Law of Thermodynamics

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Re: Argonne researchers posit way to locally circumvent Second Law of Thermodynamics

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Could have sworn that one of the tricky things about that law was that while it may appear that you are decreasing entropy locally, you are just increasing it somewhere else, thus entropy still increased in aggregate.

Why do you have to swear? We (lifeforms) are living, breathing examples of that concept.

Ironically someone downvoted you for this comment. I guess that they didn't understand how exactly true your statement is.

In essence the entire biosphere is a giant heat engine, mainly fed off of the flow of energy from the Sun to Earth to outer space, and in some extreme environments fed by the radiation of heat out from the core of the Earth. Shut off those flows of energy, and the second law would shortly catch up to us and we'd all perish.

Re: Argonne researchers posit way to locally circumvent Second Law of Thermodynamics

#13
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Someone smarter than me: why is this totally bullshit and will never work?

The second law of thermodynamics just follows from statistics and a large number of interacting particles. It's not actually inviolable as the article says. There are whole books written about far-from-equilibrium thermodynamics, and the fluctuation theorem quantifies the probability of entropy increasing https://en.wikipedia.org/wiki/Fluctuation_theorem

Right, the second law simply is a result of selecting a result from a probability distribution that increases entropy, but drawing from tails of the distribution aren't impossible, only highly improbable.

Re: Argonne researchers posit way to locally circumvent Second Law of Thermodynamics

#14
post #3

Could have sworn that one of the tricky things about that law was that while it may appear that you are decreasing entropy locally, you are just increasing it somewhere else, thus entropy still increased in aggregate.

Yeah. The impression I get from this article (which is pitifully short on specifics) is that they're going to exploit some of the seemingly-nonlocal properties of QM, like quantum teleportation.

So, a normal refrigerator decreases entropy in one region and increases it in another, but they're directly adjacent regions and the entropy (heat) is moving from one to another along a simple, everyday path (like a heat exhaust tube). It sounds like the researchers have proposed using some quantum-teleportation-like trick to have the heat show up in some unconnected region of space.

Re: Argonne researchers posit way to locally circumvent Second Law of Thermodynamics

#15

Countdown to a sci-fi movie where this idea is only half understood and the "proof of concept" device opens a portal to hell, where we meet the real Maxwell's demon... Now that I've typed this, I want to see it happen.

Use a recurrent neural network to generate said script!

Re: Argonne researchers posit way to locally circumvent Second Law of Thermodynamics

#16
I recall having an idea at least a bit similar to this years ago when I was heavily studying evolutionary informatics.

Some particularly avant garde types in that field have posited that the universe rather than having two constituents -- matter and energy -- has three primary first-order constituents. The third is information. Information is not merely an epiphenomena of matter and energy but a primary "thing."

If that is the case then there should be an E=mc^2 type equation that relates matter to information and energy to information and all three should be interconvertible. It would then further follow that energy can be converted into information and vice versa in the same way that matter can.

I then imagined a Dyson swarm of solar power satellites that produce a data stream encoding the energy they collect. This stream can be subscribed to and decoded to reconstitute this energy remotely. To globally conserve energy there would have to be a two-way aspect to this -- I imagined the receiver of energy transmitting "challenges" to the swarm that are then "solved" to yield energy stored in the form of the solution. The receiver then receives these solutions and executes them to generate what in effect would look like local perpetual motion. (But in reality energy is still being conserved.) It would look like a cryptographic hashcash-style challenge-response system with proof of work, but the energy input of the POW function can be reversibly extracted elsewhere.

If such a thing were possible and sufficiently efficient and could function in the presence of high latency, this could power a starship among many other things. If it were latency-tolerant it might also be a way to store energy. Save your laptop's power to its hard drive.

It reminds me a little bit of the "telematter stream" propulsion system from Peter Watts' Blindsight.

Re: Argonne researchers posit way to locally circumvent Second Law of Thermodynamics

#17
post #2

Someone smarter than me: why is this totally bullshit and will never work?

Haven't read the paper, but it sounds like they just rediscovered the microcannonical ensemble (but for quantum mechanics). Probably works, probably hard to do anything interesting with it in the near to medium term.

Re: Argonne researchers posit way to locally circumvent Second Law of Thermodynamics

#18

Countdown to a sci-fi movie where this idea is only half understood and the "proof of concept" device opens a portal to hell, where we meet the real Maxwell's demon... Now that I've typed this, I want to see it happen.

If so, one can't get into or out of hell unless you're going this fast.

Re: Argonne researchers posit way to locally circumvent Second Law of Thermodynamics

#19
From the publication itself:

> Note that in the discussed example the reservoir acts as some quantum analogue of the classical Maxwell demon. Namely, having been prepared in a special state, the reservoir is able to decrease the entropy of the system without the energy exchange with it, and can be referred to as a ‘quantum Maxwell demon’ […] In what was discussed above, an electron interaction with the quantum spin does not induce any correlations between the electron and the spin and, therefore, no classical correlations are present. Hence an important distinction between how do quantum and classical Maxwell’s demons operate.

So, it sounds like the "refrigerator-at-a-distance" (and thus energy transmission, when combined with a heat engine) actually (1) is more of a battery, and (2) doesn't interact with classical systems.

Is my reading correct?

Re: Argonne researchers posit way to locally circumvent Second Law of Thermodynamics

#20

Countdown to a sci-fi movie where this idea is only half understood and the "proof of concept" device opens a portal to hell, where we meet the real Maxwell's demon... Now that I've typed this, I want to see it happen.

Wasn't that the plotline in the most recent Doom game?
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