The Search for Perpetual Motion

Perpetual motion has been a sort of holy grail of science since the discovery of momentum, inertia, velocity, and similar ideas from classical physics (electromagnetism gave it a major boost).  Around the same time though, the Laws of Thermodynamics were conceived, which state that perpetual motion machines are impossible, because the energy in a closed system cannot increase, and entropy cannot decrease, which means that any organized motion will eventually decay to nothing as it radiates thermal energy (from friction, in most cases).  This proof, however, has not stopped the search.  Any kind of working perpetual motion machine would prove that it is possible for a closed system to either increase in total energy or at least for entropy to decrease, and this essentially means that we could create devices that would create free energy.  This is, essentially, a search for gold, and many people are willing to doubt the proof against it if there is a promise of riches at the end of the rainbow.  Of course, this search is so absurd that the U.S. Patent Office will not even consider patents for perpetual motion machines.  Until about 10 minutes ago, I was of the opinion that we would be better off if everyone would just give up on this fool's errand and do something useful with their time.  What happened 10 minutes ago, however, is that I realized several things.

The first thing I realized is that science cannot prove anything definitively (I already knew this, but I applied it to this problem in that moment).  The closest science can get to proof is to disprove all other possibilities, but even then, it stands on shaky ground.  The fact is, science proves things by observation.  The Laws of Thermodynamics are not literally proven physical laws.  They are statements about what has been observed.  The Laws of Thermodynamics state that we have never observed conservation of energy to be violated and we have never observed entropy to decrease in a closed system, given an enormous number of observations.  This is the closest science can get to proof, but it does not mean that it can never happen.  Perhaps there is some very specific situation where conservation of energy can be violated or where entropy can decrease in a closed system.  Until every possible situation has been tested, the Laws of Thermodynamics are just widely accepted theories that apply to every situation that has been tested.  In other words, we don't actually have solid proof that perpetual motion and free energy are impossible.

Now, I don't want to imply that I think perpetual motion is possible, and I certainly am not trying to suggest that we should put more resources into this endeavor.  Given how much effort has been spent on this without any progress, odds are that even if it is possible, the situation required is so complex or otherwise difficult to discover that we will probably never discover it.  Of course, it is also possible that we just don't have the technology to do it, but if this is the case, it will likely be solved as soon as we develop that technology.  The fact is, it probably does not matter if perpetual motion is possible or not, because we probably would have found it already if it is something we have the means to do.

The second thing I realized is that the work done on perpetual motion machines has produced value.  A great number of very useful inventions have drawn from discoveries and ideas found while trying to make perpetual motion machines.  Now, I said that we probably don't need to put more resources into this search, but this is where more resources might really produce useful things.  In fact, we are already seeing useful ideas come from the search for free energy, beyond just perpetual motion.  There are many people experimenting with "crystal cell" batteries that seem to be able to continuously produce very small electric currents for far longer than standard batteries can last even in storage.  The hope is that these batteries can be improved and scaled up to produce large amounts of energy for very long periods of time, but even if this fails, there are plenty of applications for very long life, low current batteries, and the number of applications will only increase as we improve the energy efficiency of technology.  As long as people are constantly trying new things, we will see new discoveries, even if the end goal is impossible.

There are two reasons we should continue the search for perpetual motion and free energy.  The first is that maybe it is possible, and we have just not found it yet.  The second, more important reason, is that this search can provide us with very valuable knowledge and discoveries, even if we never reach the goal.  This second reason may even be sufficiently valuable to encourage or even help fund the search.