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Todd Duncan wrote:
> Hi everyone,
>
> I've written up a little paper based on the "energy" talk I gave a few
> weeks ago, and it's in html format at
> http://www.scienceintegration.org/Concepts/essay1.html. Sorry for the
> delay in getting that finished and posted.
>
> Todd

Thanks, Todd. Your paper is quite interesting. Now I think it is time to resolve the dissipation problem: Does really energy take forms less and less useful, with time? In the chemical world, this does not seem to be the case. Roughly, half of the reactions are exothermic - for a spontaneous exothermic change, more useful energy (the energy of chemical bonds) is converted into less useful (heat). However, the other half are endothermic - for a spontaneous endothermic change, less useful energy (heat) is converted into more useful (chemical bonds). And there is no evidence whatsoever suggesting that the world is becoming more exothermic.

By the way, the second law turns out to be a logical mistake made by Clausius and Kelvin (I have already written something about that). Carnot rigorously deduced that, if heat cannot be converted into work (because it is an indestructible substance, calorique), ALL REVERSIBLE HEAT ENGINES WORKING BETWEEN TWO GIVEN TEMPERATURES HAVE THE SAME EFFICIENCY (Carnot theorem). Clausius and Kelvin rejected the assumption (heat CAN be converted into work), but wanted to preserve Carnot theorem. Why? Just a matter of interest - Kelvin had already based his famous universal temperature scale on the Carnot theorem, and Clausius was in the process of coining the concept of entropy which also depends on the validity of the Carnot theorem. So they had to find, ad hoc, some other principle (not CALORIQUE) from which Carnot theorem could be deduced. How? If Carnot theorem were wrong, Clausius argues, the simultaneous working of two reversible machines with different efficiencies would amount to transfer
of heat from a cold to a hot body, and "this contradicts the further behavior of heat, since it everywhere shows a tendency to smoothen any occuring temperature differences and therefore to pass from hotter to colder bodies" (cit. Clausius).

The above argument is misleading. In fact, there is an implicit assumption in Carnot proof - the reversible machines he dealt with (as well as all other reversible machines) can only work in the presence of an operator - someone who at least sets the machine in motion. So, logically, Carnot theorem IS indeed a corollary of

A) Even in the presence of an operator, heat cannot be transfered from a cold to a hot body.

This would be the correct second law, but, unfortunately, it is not an experience of mankind. So Clausius ignored the operator and devised

B) Heat cannot pass from a cold to a hot body, in the absence of other changes in the system or the surroundings.

The statement (B) is already an experience of mankind, but, unfortunately, it has nothing to do either with (A) or with the Carnot theorem. I am sorry I cannot present the whole story - it is extremely interesting to deduce all the thermodynamic concepts from this "little trick" of Clausius and Kelvin.

Pentcho