Jim Baen's Universe

NonFiction articles

My Father's Watch

Written by Stephen Euin Cobb

If you thumb through a new and freshly printed physics textbook from any university on Earth, you will be looking at the culmination of centuries of careful work by thousands of dedicated scientists; such a book is a treasure beyond description, easily comparable to the lost library of Alexandria. If you doubt this valuation, imagine what price it would bring if you could take it back in time a hundred years. Or conversely, what would the large governments of the world pay right now for a similar book published a hundred years in the future?

But as wonderful as is the information in a new physics textbook, someday it will all have to be rewritten. Some chapters will be rewritten within decades, some may take millennia, but all will require change.

This is because every scientific explanation of the physical world, whether we call it a theory or a law, eventually has to be modified to remain accurate under conditions that were not foreseen by its original creator. Newton's laws of motion were correct until we applied them to velocities near that of light or within a powerful gravitational field. Under those conditions, Newton's laws are now superseded by Relativity. And Relativity also was correct, until we discovered such things as the wave nature of particles and instantaneous action at a distance which is where quantum mechanics now supersedes Relativity.

Because we are continually applying them to new and untested situations, every law and every theory must eventually be adjusted. So while it would be comforting to pretend, for example, that the laws of thermodynamics are greater than the laws of Isaac Newton and will never need adjustment as his did, it would also be naive. Eventually we will discover places and situations where they do not apply as we understand them today.

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When I was in my early twenties, during the second half of the nineteen seventies, my father got a new watch and gave me his old one. Thrift is a concept that runs strong in my family. An item no longer needed is not thrown away; instead, you look around and find someone who can use it and you give it to them. I suppose this is a form of recycling, but that's not the point.

The point is that old watch, with its two tiny bits of welding spatter melted permanently into the glass which covered its dial, never needed winding. The natural movements of the wearer's wrist during the course of a day would wind the mainspring.

This was done by a simple device hidden inside: just a little weight mounted on a rocker arm. When the rocker arm pivoted to the left a spur caught one of the gears of the mainspring and rotated it, tightening the mainspring a very tiny amount. When it pivoted in the opposite direction the spur slid across the gear without catching and so did not rotate it in the opposite direction which would have loosened the mainspring.

That these ratcheted back-and-forth pivotings of the rocker arm occurred at random did not matter. By pivoting thousands of times during a day, the rocker arm tightened the mainspring to its limit and kept it there.

For centuries, simple devices like that have sparked the minds of naive inventors with the dream of designing a magical machine that would run forever. Usually this dream machine was powered by the very same momentum which it produced. Technically, this would make it the mechanical equivalent of an audio feedback loop, a physical manifestation of a vicious circle.

The designer's naivety was, of course, displayed in the failure to understand that all machines are subject to friction. Usually this friction is created as surfaces rub against one another in bearings or gears, and sometimes it is a product of electromagnetic induction, in which the free electrons (those not bound in atoms) within wires or other metal parts are shoved around within those wires and metal parts and, by being shoved, rub against the substance of the metal itself, producing the form of friction we call electrical resistance. In cases where metal parts have an irregular geometry, free electrons are sometimes shoved into a corner or narrow place within the part from which they cannot escape, and by being squeezed together, produce a static electric resistance as well.

Friction is universal. Human beings have never made any device that was not subject to friction.

Even on the nanoscale, friction is universal. But while some things are the same down there, some things are very different.

For example, on the scale at which we human beings experience things—sometimes called the macroscale—"temperature" is a mysterious quality of substances that we can feel, but which usually remains invisible. If, however, you could see things on the nanoscale "temperature" would be neither invisible nor mysterious. On that scale it is the obvious and random physical motion of individual objects and/or the vibration of their parts.

Only by reducing temperature to absolute zero will things actually stop moving and vibrating. This is because temperature is defined as the amount of movement or vibration on a molecular, atomic or subatomic level. Temperature and movement are not similar or somehow related; they are the same thing exactly.

On the nanoscale, random motion and vibration are universal and unending. On this scale there is never a pause and