The question sounds kinda dumb when I say it out loud but at the same time I'm very curious. When things break, is it solely due to an intrinsic design flaw or is it due to entropy? And is the machine that never breaks analogous to a perpetual motion machine?

To clarify my question take computer hard drives. If I'm not mistaken, they used to write to a spinning disk, but the moving parts would inevitably erode. Then they came out with ssd but heat would eventually corrode the transistors. So is it possible to make some design that lasts forever (with continued use)?

  • $\begingroup$ This is an interesting question but I think you should carefully define what you mean by machine. Would an organism fit your idea of machine? $\endgroup$ – a_a Dec 17 '15 at 6:44
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    $\begingroup$ Yeah, it's called Murphy's Law :-) $\endgroup$ – Carl Witthoft Dec 17 '15 at 14:51
  • $\begingroup$ Murphys law, that's funny. $\endgroup$ – user3256725 Dec 19 '15 at 18:00

It is at least certainly a law of engineering ;-)

Never and infinity is a strange place; I would say, everything that is not repaired by a system does break down at infinity. Things like radiation, non-pure vacuums, non-pure materials, Heisenberg uncertainty, and other crazy physics we don't understand yet, degrade engineered systems with some amount of background entropy we can not control.

That said, we can get very close :-) In mechanical engineering there is a concept called infinite life. It basically means that a material(usually metal) is not stressed beyond its purely elastic region. In practice if it can survive 1 million cycles it is considered "infinite". In an exaggerated example; if I machined a stainless steel door stop, it would probably continue to stop doors in excess of 1 million cycles. It is way over engineered for the task we require of it; so provided they still use doors in the future it would last for millions and millions of years.

One story I heard a long time ago talked about making a lathe with a wooden screw carved by hand. Using that wooden screw inside the lathe as a component you were able to turn a better screw out of wood. Then put that screw in the lathe and turn a better one out of metal and so on. Though I am not certain how well that would really work in practice; the principle is that we can achieve a higher degree of precision and engineering beyond the precision our tools were built with. An individual component can not beat an infinity of entropy, but a system can.


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