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James Jeans

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Another conspicuous failure of classical mechanics was with one aspect of the problem of radiation. ...Imagine a crowd of steel balls rolling about on a steel floor. ...There must... be a steady leakage of energy from... causes, such as air resistance and the friction of the floor, so the balls will eventually lose energy, and, after no great length of time, will be found standing at rest on the floor. The energy of their motion seems to have been lost... most of it has been transformed into heat. The classical mechanics predicts that this must happen; it shows that all energy of motion, except possibly a minute fraction of the whole, must be transformed into heat whenever such a transformation is physically possible. It is because of this that perpetual-motion machines are a practical impossibility.

 
James Jeans

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Precisely similar ideas are applicable to the molecules that form the air in a room. ...The classical mechanics now predicts that the whole energy of motion will be changed into radiation [heat], so that the molecules will shortly be found lying at rest on the floor... In actual fact they continue to move with undiminished energy, forming a perpetual-motion machine in defiance of classical mechanics. ...We have passed from one to another of three worlds... from the man-sized world to the world of the electron.

 
James Jeans
 

I am impelled to one further reflection, dealing with the conservation of energy. We say, with truth, that energy is transformed but not destroyed, and that whenever we can trace the transformation we find it quantitatively exact. So far as our very rough exactness goes, this is true for inorganic matter and for mechanical forces. But it is only inferentially true for organized matter and for vital forces. We can not express life in terms of heat or of motion. And thus it happens that just when the exact transformation of energy will be most interesting to watch, we can not really tell whether any fresh energy has been introduced into the system or not. Let us consider this a little more closely.

 
William Crookes
 

The production of motion, molar or molecular, is governed by physical laws, which it is the business of the philosopher to find out and correlate. The law of the conservation of energy overrides all laws, and it is a preeminent canon of scientific belief that for every act done a corresponding expenditure of energy must be transformed.
No work can be effected without using up a corresponding value in energy of another kind. But to us the other side of the problem is even of more importance. Granted the existence of a certain kind of molecular motion, what is it that determines its direction along one path rather than another?

 
William Crookes
 

This fallacious result is not... a peculiarity of classical mechanics; it is given also by a very wide class of possible systems of mechanics. This being so, no minor modification of the classical mechanics can possibly put things right. Something far more drastic is needed; we are called upon to surrender either the continuity or the causality of classical mechanics, or else the possibility of representing changes by motions in time and space.

 
James Jeans
 

The universe is composed of matter, and, as a system, is sustained by motion. Motion is not a property of matter, and without this motion the solar system could not exist. Were motion a property of matter, that undiscovered and undiscoverable thing, called perpetual motion, would establish itself. It is because motion is not a property of matter, that perpetual motion is an impossibility in the hand of every being, but that of the Creator of motion. When the pretenders to Atheism can produce perpetual motion, and not till then, they may expect to be credited.

 
Thomas Paine
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