Is it possible to create an inexhaustible energy source?

Um...you may want to re-check your math there. That's not possible.

^ Yeah, friction.

Even assuming no friction, you can't get any more energy out of it than you put in. Friction is essentially an engineering challenge, but conservation of energy is universal and built-in.

So the only true way to make it work is to add magic then?

Yes. Or to exploit something like nuclear which isn't actually breaking conservation of energy (the energy's all there in the nuclei) but looks kind of like it is because none of our experience tells us that, say, uranium has all this energy stuck inside it.

Or to just... bend physics a little. To have a slightly botched scientific answer. So that it's not just "magic". Use some Unobtainium that's Phlebotinum.

edited 18th Apr '12 3:04:05 PM by AmazingLagann

See, gravity, which thusfar hasn't shown to be exhaustible, would pull the ball down, and the ball would conveniently always be on a slope, pretty much just harvesting the endless energy that's already there.

Again though, this is hypothetical.

edited 20th Apr '12 12:36:06 AM by thatonedude

Draw the diagram and I'll believe you.

I believe it would be something like adding a Slinky to this.

I'm not sure if you already realize this, but that image is an optical illusion; the physical object it represents cannot exist.

To derive energy from gravity, you must move closer to a massive object. You cannot derive infinite energy from gravity, because eventually you'll reach the massive object and not be able to get any closer.

x4 That sounds like Troll Science. Would a perfectly round object (let's call it "ball" on a perfectly round World not have the gravitational forces that act upon it even out by the fact that every point of the ball would have a point mirroring it relative to the plumbline with the same amount of force applying. Thus the ball should just lie there.

That was the point. An eternal slope is pretty much the same thing in theory.

I've seen some sci-fi works in which they had developed Singularity Power, which derives energy from a simulated Black Hole.

Not sure how that works exactly, but it's far more powerful and cleaner than Nuclear Power. Also, I've only ever seen it twice. First in Sid Meier's Alpha Centauri (which is where I got the term), in which Singularity Power Sources could be used as global power sources. Also, in Doctor Who, the TARDISes developed by the Time Lords derived power from a simulated Black Hole on Gallifrey called The Eye of Harmony, and there was one time that the Daleks had built and android powered by an Oblivion Continuum, which is a captured wormhole.

The technology required to utilize that sort of power would be incomprehensible to human scientists today, so it would have to be exclusive to far-future settings or Sufficiently Advanced Aliens.

Are those actually inexhaustible, or just have a so huge capacity it's not even funny anymore and there's really no practical difference from inexhaustible?

What you can do with a tame black hole is keep feeding it garbage and catch the Hawking radiation it emits. That turns the matter of the garbage into energy with ~100% efficiency, and you can also get some extra with accretion disk acceleration/gamma emission. Of course, you've got to keep the black hole at precisely the right size, since the rate of Hawking emission is inversely proportional to mass; if you let it get too small, then it'll cascade and try to emit all its mass at once, which is a phenomenon more familiarly known as "a huge fucking explosion". It's not got the same quality as a fission plant, wherein you don't have to do much and it just keeps putting out power until it exhausts the uranium in twenty years; it's most definitely a high-maintenance thing. However, it will give you pretty much free energy once you get it running; you just have to keep a constant flow of mass into it.

Another issue is that the black hole has to be quite large so that the output isn't hard gamma radiation. (which is stupidly hard to absorb)

In my understanding of Einsteinian physics, gravity is not a force, but a curvature of spacetime. It doesn't pull you, your path through space is warped toward an object, and that warping is greater as the mass of the object increases.

Sure, but in our usual everyday definitions of things we can just call it a force.

So I'll just say that the coal is made of alien substance that makes it burn without "losing" itself and only the heat of the sun can totally burn it all up!

Sort of related question. Diamond is coal. How well and how long does it burn?

The major difference between diamond (100% carbon) and anthracite coal (90% carbon) is the allotrope; the composition is nigh-identical. That being true, I can't imagine that diamond would burn that much fundamentally better. I'm not actually sure how diamond would burn; the allotrope might prevent oxidation from being easy.

Re: coal: that's an egregious misunderstanding of how combustion works. You can't make anything that will 'burn' in the conventional sense and yet not be consumed. If this is explicitly a magic universe in which things are meant to make symbolic rather than scientific sense, you could get away with it; in any sort of sci-fi, you can't. (The reason being that the mechanism behind something burning is the material of it being stripped away and combined with oxygen, leaving heat behind that was formerly bound up in the molecular bonds; the process is not coherent without the consumption of the fuel. That would be more like some sort of strange heat-initiated exothermic air catalyst, which would have to break conservation of energy and would be nothing like what any scientist things of as 'burning' anyway.)

OP: Just use Exotic Matter/Negative Mass/Dark Energy. Say your space meteor has some sort of inexplicable property that condensed Dark Matter enough to be usable as an inexhaustible energy source. Yeah, it's mostly speculative, but it'll be somewhat higher on the scale of scientific hardness than any other answer so far, which have been basically telling you to use magic.

So essentially even with it being a space rock it can't be used as an excuse?

That works. The setting is Cattle Punk anyway with iron trains becoming Humongous Mecha powered by said unending coal.

Is there really a reason it needs to be unending? Fighting over dwindling resources of magical space rocks could make for a pretty cool plot point, and could work well with a 'gold rush' theme. Just saying.

Yeah, stuff like black hole generators, dark matter manipulation, or Phlebotinum produce more power than anyone IRL knows what to do with. It might as well be infinite, despite not actually being so.