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Posts Tagged ‘thermodynamics’

This is an easy one to address. I haven’t seen it being seriously argued anywhere lately, which might mean that it’s finally sinking in what nonsense it is, but maybe I’m just looking in the wrong places. Either way, it doesn’t take much to understand why the theory of evolution is in no way refuted by the second law of thermodynamics.

Without getting too sciencey (because heaven forfend that this blog ever actually becomes informative), the law says that the total entropy of the universe is always increasing. Entropy, as I’m sure you all remember from your physics PhDs, is a measure of disorder, or chaos – so the law essentially states that things are always getting messier. Everything tends toward randomness, and for things to spontaneously sort themselves out into a non-random pattern – for the milk to unmix itself from my tea, for instance, and sit on the top in a separate layer, or for a dropped heap of sand to simply fall into a magnificent castle, complete with turrets and drawbridge – is impossible.

Except, not quite. Although the universe’s total entropy is increasing, that doesn’t mean that every single point in it must be getting more and more random and disordered all the time. It’s possible to decrease entropy locally, in some small system, by doing some work (adding some energy) to bring some order to the proceedings. It is possible to build a sandcastle, obviously. You just have to provide some process by which effort is expended, and the sand is arranged into an ordered pattern – such as, pick up your spade and get to work.

It’s silly to think the law means that nothing can ever become more complicated. You can see examples everywhere of complicated and intricate systems arising out of simpler ones. You can take a pile of CDs strewn haphazardly across the floor and alphabetise them; you can plant an acorn, and watch a complete oak tree grow (though only if you have a hell of a lot of spare time).

The point is that these sandcastles and acorns aren’t all there is – in each case, there’s something outside that small system, providing the work that needs to be done to put things in order. For that to happen, the entropy outside needs to increase, so overall things are more chaotic, even if a small patch of organisation breaks out somewhere.

It’s easy to see how this applies to something like evolution. Organisms do increase in complexity and orderedness (which sounds like it should be a word) over time, but like the acorn growing into an oak tree, the rest of life on the planet takes in energy from various environmental sources, particularly the Sun. We’re more complex and less disordered than our ancestors, but increased entropy levels elsewhere mean that the thermodynamics police won’t be needing to make any arrests. Chaos in the universe overall is behaving as it should.

PZ Myers has some actual numbers on roughly how much energy the Earth would need to be provided with to account for the increasing complexity of evolution, and the actual energy it’s provided with by the Sun. Guess which one’s bigger.

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After the roaring success of similar campaigns for both Tibet and Willy, it’s now time to discuss Free Energy. (Ha.)

The idea of free energy is pretty much what it sounds like. It doesn’t just work in the “free cable” sense of tapping into someone else’s pipeline, but rather by actually creating new and usable energy, often literally from thin air. It’s like taking candy from a baby, then selling it to another baby, then stealing it back again, and repeating the pattern indefinitely.

These kinds of machines which promise ultimate power at low, low prices are still a recurrent phenomenon, and make for pretty big business. Perhaps it’s not surprising that people regularly claim to have invented or discovered some device, mechanism, or physical process which would render that whole fossil fuel problem moot. It’s an appealing notion, to have something which could power itself and let you siphon off the overflow, storing and using all this new energy as it spills out from… somewhere. Unfortunately – at least, if you’re living under Homer Simpson’s roof and obey the laws of thermodynamics – the Universe places an inconvenient embargo on the whole idea.

Although there might seem to be many ways you can “get” energy where there wasn’t any before, you’re never really conjuring anything out of nowhere. If you light a match, you’ll be releasing heat (thermal energy) that wasn’t around before, but it comes at the cost of the resources you’re burning. The amount of energy released in the flame exactly matches the lost energy that existed in a different form in the chemicals that made up the match.

Calculated in this broader, chemical sense, energy isn’t something that can ever be created or destroyed, but only transferred from one state to another. If you burn some oil for energy, you can’t keep the oil and burn it again. If a system is kicked into action by something falling, like water in a water wheel, then it would take at least as much energy as you got out of it if you wanted to raise the stuff back up to its original height again. (This is why Wikipedia’s gallery of perpetual motion machines are all doomed to failure; a system can’t, by itself, generate more energy than it uses to keep itself going indefinitely.)

Them laws of thermodynamics ain’t no slouch, incidentally. The first one – pretty much the “no conjuring” rule as described above – is among the most solidly convincing theories in modern science. If you throw that out, then a whole lot of really useful physics goes with it. Centuries of sophisticated learning and understanding shouldn’t be scribbled over with the first new and crazy idea to come along with Earth-shattering claims.

However cunningly you try and arrange something with magnets to keep propelling itself around on its own metaphorical steam, it can’t be done.

If a flywheel is spinning, and seems happy to keep on doing so pretty much indefinitely (some are set up with such low friction that their rundown time is measured in years) then that’s all well and good, and may be a useful way of storing energy, such that it can be usefully transferred from one form to another. But to get any energy out so that you can use it, you need to let the flywheel push against something else to power it – and in so doing, you’ll be exerting a similar push against the spin of the flywheel, causing it to slow down from the friction. The energy you get out can never be more than the energy you had to put in to get it spinning that fast in the first place.

If you want to run a car on water, you’re going to have to do something more than Stanley Meyer did, because if all you’re doing is separating water into the oxygen and hydrogen that it’s made of, then burning the hydrogen and oxygen to make water again, you’re never going to get any more out when it burns, than you needed to put in to separate them. You just go round in circles, and no work is being done.

Unless, y’know, you’re throwing out almost all of physics again. That site describes the problem of how do it “economically”, and says that by traditional methods the car “could not recharge from the process quickly enough”, but makes it sound like levels of energy input and output are two separate issues to be improved upon. They don’t seem to mention the thing about needing more than 100% efficiency, which makes recharging from the process “quickly enough” about as likely as being able to run fast enough to overtake your own knees.

Creating energy this way would be like magicking water into existence by taking some water, freezing it, then melting the ice, and experting to find more water than you started with. It’s not going to get you very far. You don’t get something for nothing.

Admittedly, not every device needs to get something from nothing, while still being intended to revolutionise the world of making stuff go. Wikipedia lists several resource-consuming machines which provide apparent perpetual motion, like that little drinking-bird thing that helped Homer keep the power plant safe while he went out to buy a muu-muu. (Huh, lot of Simpsons references in this entry. Well, two.) The way those work is surprisingly sophisticated, and there’s some fascinating science behind subtle sources of energy like ambient temperature gradients, or pressure from photons.

This isn’t any kind of a loophole around the laws of thermodynamics, but maybe you don’t need to circumvent them, if energy can be grabbed from plausible sources, in such quantities that it might seem effectively free to us. I can’t rule that out, but the problem then comes back to the perennial sticking point: if you want to be taken seriously, publish some damn science. If you actually do an experiment, and find something to support your claims, and then tell other people what you did so that they can try it too and see if you’re still right, then vindication surely awaits. But what you’re saying sounds unlikely, and it sounds very similar to some other unlikely-sounding things, which are demonstrable nonsense and which break many well established laws of science. You’re going to have to actually show us something impressive.

Of course, there are always reasons why they can’t do that just now, often relating to the various conspiracy theories in place to suppress the knowledge of this world-changing technology, and preserve the status quo for those who find it profitable. I’m not aware that any significant evidence has ever been presented that this is actually happening – of course, this could mean that it’s all been covered up, but it could more simply mean that it was never there. (More on conspiracy theories in general over here.)

I’m sticking with my “publish some damn science” argument. I don’t see how data from every scientific lab could be kept out of every respectable scientific journal – those scientists and journals would be fascinated to learn anything new that’s well supported (that’s kinda what science is, after all), even if some politicians and oil magnates wanted it kept quiet.

But when established science is so strongly indicative that you’re full of shit, in a field with a history of fraud (and other business practices which should maybe raise a suspicious eyebrow), we’re going to wait for some actual evidence before accepting that you, unlike the conmen and failures who’ve gone before, really have revolutionised everything we understand about the Universe. And while everybody seems cagey as to how these things are supposed to work, and what tests might be done to find out whether they really do, and while Reuters reports credulously on supposed new developments, we’re going to keep doubting that The Man is keeping you down.

Science loves discovering things which it can’t explain, and which shatter old paradigms. Find us some actual evidence, or even just show us what’s going on and let us find it, and the scientific and skeptical community will totally be on your side. Stop holding press conferences and asking for more and more research money. It’s not working.

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