Monthly Archives: December 2009

The myth (of the myth) of perpetual motion

Lately I’ve been thinking about two seemingly unrelated—but actually very related, in my opinion—topics: perpetual motion, and immortality.

Perpetual motion is a concept that relates to science, or science-fiction, depending on whom you ask. It is not the same as “overunity,” though many people mistakenly treat the two ideas as interchangeable (and even though searching for “overunity” on Wikipedia takes you directly to the article on perpetual motion). First of all, I want to explain the subtle difference between these two concepts. Then I’d like to talk briefly about why I have a problem with those who dismiss anyone who claims to have developed a new technology, overunity or otherwise, that supposedly violates the “laws of physics.” Lastly, we’ll get into this whole immortality business. But first things first.

Some people probably aren’t familiar with the term overunity. Fortunately, it’s quite easy to explain. Take any machine that does work, and you’ll find that it requires a source of energy: cars need fuel, stereos need batteries, animals need food. Even a simple lever or pulley requires some agent to exert force in order for it to accomplish anything. Without an energy source, no work can be done. But then what happens to this energy? A naïve guess would be that it is simply “used up”; but that is not really the full picture. Energy is converted from one form to another: when something moves, that’s kinetic energy; when something heats up, that’s thermal energy; and so on. The key point to understanding overunity is this: according to our modern understanding of energy, it is never actually gained or lost. It isn’t “used up,” in other words; it’s simply changed. For this reason, every machine that does work can be assigned an efficiency rating from 0 to 1, measuring how much of the energy put into the machine is actually used to do the desired work (versus how much of that energy is converted into essentially useless forms, such as heat).

By now you can probably guess what overunity is, if you didn’t already know: it’s the property of a machine utilizing more energy than it’s given to accomplish its work—or, to put it another way, “producing” energy—thereby earning an efficiency rating greater than 1 (hence, over-unity). It is widely assumed that if an overunity machine were ever created, it would be, ipso facto, a perpetual motion machine, one that can demonstrate continuous motion without ever stopping.

The operative word here, and the key to the “subtle difference” I referred to earlier between perpetual motion and overunity, is “ever.” A perpetual motion machine is one that never stops. That’s not the same as an overunity machine. But before I explain why, let me briefly go on a tangent.

The whole reason I’m discussing this is that there’s this company, Steorn, who claim to have developed an overunity machine. They actually made this claim a few years back. Of course, plenty of companies and individuals before them have made the same claim; but what sets Steorn somewhat apart from the pack are their brashness and their persistence: they didn’t just say, “We’ve achieved overunity”; they placed a full-page ad in The Economist, commissioned a jury to validate their technology, staged a public demo in 2007 (which didn’t work out so well), endured a seemingly endless stream of ridicule from the tech community, and somehow to this day have never rescinded their initial claim or ceased work on this alleged overunity technology of theirs, which they call Orbo.

In fact, this week Steorn are currently hosting a new demo of Orbo, and this time they’re actually not crashing and burning—though they’re not exactly soaring, either. Apparently Orbo 2.0 features a battery which powers it. (Steorn’s assertion is that the Orbo is creating enough power to recharge the battery while the battery provides the energy necessary to make the device spin—sort of a quid pro quo arrangement.) This naturally elicits smirks from the skeptics, who not-so-unfairly interpret the presence of a battery as proof, or at least very strong evidence, that Orbo is not an overunity device. But then, to the skeptics, Orbo was impossible from the beginning, because it violates the Second Law of Thermodynamics.

Personally, I take issue with that. Now I don’t want to give any false impressions: I don’t really believe that Steorn have what they think they have, either. But I wouldn’t say it’s impossible. To declare anything “impossible” from a scientific viewpoint is, to be blunt, ridiculous. There is no such thing as a scientific “fact,” and anyone who says otherwise is deeply misguided about either what it means to be scientific or what it means to be a fact. The premise underlying all of science is that we can continually reformulate our understanding of the world through observation and the accumulation of empirical evidence; it is this constant reformulation that drives science and makes innovation possible. With this in mind, it is clear that there can never be a true “fact” in the eyes of science; rather, what we have are a set of theories that have grown out of years, decades, even centuries of observations. Some of the most vigorously tested of these theories are commonly referred to as “laws,” like the Laws of Thermodynamics; but even these are not facts. They are phenomena that have been witnessed hundreds, thousands, even millions of times.

Consider this: when Newton wrote the Principia, his most seminal work, he established theories of mechanics that, if it weren’t for Einstein, we might still treat as “fact” to this day. Newton’s formulas for force, momentum, acceleration, and all that good stuff were (and are) extremely useful approximations of the real-world phenomena we observe. They enable us to make testable, repeatable predictions about the outcomes of a vast range of experiments with tremendous accuracy. And yet, where Newton made the assumption that time passes at a constant rate for two observers of the same incident, Einstein showed that time is variable, and our entire understanding of reality is changed as a result.

My point: Newton’s discoveries, though they provided a deeper understanding of the world than any theories of motion before his time, and even though they were empirically supported with overwhelming consistency, were not fact.

I don’t want to belabor this point more than necessary, but because it’s one I’m fond of, allow me to offer one more quick example. This is something my ninth grade biology teacher taught us that has stuck with me: even the theory of gravity is just that: a theory. Yes, it may be that every time a person has ever thrown something into the air, it has eventually fallen back down to the earth; and it may be that we are able to calculate the trajectories of distant celestial bodies with undeniable accuracy thanks to our current conception of the mechanism by which massive bodies exert gravitational attractions on one another. And yes, it may even be that our understanding of gravity is actually true. But we can never know it’s true, with 100% certainty, because all we can do is make a guess based on what we have observed—even if we’ve observed it a hundred million times. The more we observe it, the greater our confidence; that’s the whole point of science: repeatability, observability.

So I don’t give much weight to the opinions of those who say things like, “This violates a basic law of science and is therefore impossible.” Frankly, this is the same thinking that resulted in Galileo’s arrest for declaring that the Earth revolves around the Sun.

…OK, but what about perpetual motion? As I was saying, perpetual motion and overunity are two different things. To understand what the difference is, think again about the definition of overunity. An overunity device is one that outputs more energy than it receives. Is this the same as moving forever? It isn’t, because, if an overunity device were to exist in the real, physical world, then it would exist in the real, physical world.

Interestingly, the real reason it is generally accepted that perpetual motion is simply not possible actually isn’t that overunity is impossible, though that may be widely believed as well. The reason most people deny the possibility of perpetual motion can be summed up in a single word: friction. Friction is that counter-force that basically gets in the way of everything. If you lie down on the floor of your house and try to drag yourself along your belly, you’ll find it’s a lot easier to slide along a polished wood floor than the carpet. Generally speaking, the smoother the surface, the less friction. But no material known to mankind is exempt from its effects. It’s what makes everything come to a stop, eventually.

In fact, if it weren’t for friction, everything that moves could be a perpetual motion machine. If I rolled a ball down a U-shaped ramp, and if this ball and this ramp were somehow frictionless, then the ball would continue up to the opposite side of the U to the exact same height from which I dropped it, then turn around and come back to the first side, again to the same height, and would continue on this back-and-forth path indefinitely. The reason this doesn’t happen in the real world is that some of the ball’s energy is lost from jostling the particles in the air (i.e., wind resistance) and from interacting with the particles in the ramp itself, stirring up motion and dispersing its energy gradually over time. At some point, in the real world, all of the energy in the ball would have been converted, and the ball would lie still.

Even if a machine could product its own energy, it would succumb to a similar fate. Certainly, it could last a lot longer than other machines; but over time, its parts would become worn from all the friction, from all the collisions between the particles in the machine’s parts with each other and with the air around them, and ultimately, after enough time had passed, the machine would simply break. An extremely well-engineered overunity machine might run continuously for a billion years, but it would, eventually, stop working.

And this brings me at last to what I wanted to say about immortality. A fairly popular notion in science journals and magazines today is that humanity is on the cusp of a breakthrough—the development of a longevity vaccine, our triumph over our own mortality. I’ve thought about this, and I find the idea intriguing, even exciting. But then I’ve thought, you know, even if this medicine were discovered, and we could somehow reverse our own aging process, we wouldn’t live forever. Sure, we’ve got a distinct advantage over that poor dysfunctional overunity machine I was just describing in that our bodies heal and repair themselves; but still, what about car accidents? Heart attacks? Disease? For that matter, what about war? Let’s face it: aging is not exactly the number one cause of death these days, anyway. We could discover how to stay young indefinitely and we’d still find ourselves dying.

Our bodies are, after all, like machines. If perpetual motion isn’t possible for the mechanical world, why would it be for us?

Hello world!

#include <iostream>

int main(int argc, char** argv) {
    std::cout << "Hello world!";
    return 0;
}
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