måndag 12 juli 2010

Why a Cold Body Cannot Heat A Warm Body


This post connects to previous posts arguing that backradiation is unphysical.

Recall that backradiation from atmospheric greenhouse CO2 is the scientific corner-stone of IPCC climate alarmism, supported by in particular the Royal Society and the Royal Swedish Academy of Sciences. This corner-stone is unphysical and purely fictional.

In Computational Black Body Radiation  I give a mathematical explanation of Planck's black body radiation law based on finite precision computation, as an alternative to the statistics of quanta used by Planck himself, as decsribed in my knol The Desperation of Planck.

The basic problem is to explain why and how nature avoids an ultra-violet catastrophy by cutting off radiation of frequencies higher than a certain cut-off frequency proportional to the temperature according to Wien's displacement Law (see fig above): Higher temperature allows higher frequencies to be radiated, as seen in the color of a fire changing with temperature.

Planck explains the cut-off using statistical mechanics by viewing radiating waves to be assembled from a certain smallest unit of energy (quanta) and assuming that high energy/frequency is rare because it requires assembly of many quanta. 

In Computational Black Body Radiation I propose an alternative explanation viewing radiation the result of a form of analog finite precision computation (performed by oscillating 
atoms/molecules) with the precision being proportional to temperature (mean oscillation amplitude) leading to high frequency cut-off.

Higher temperature means larger oscillation amplitudes, which allows sharper expression
or higher precision. Stated differently: Low temperature whispering is prone to large errors. 

The explanation of cut-off by finite precision computation offers an explanation of the 2nd Law of Thermodynamics expressing that heat/radiation energy by itself can be transferred from a warm to a colder body, but not from a cold body to a warmer.  Why is it so?

Because in transfer from warm to cold, high precision/energy/frequency waves are transformed to low precision/energy/frequency waves.  In short, high precision can transformed by itself (with low precision) to low precision. 

On the other hand, transfer from cold to warm, would require low precision to be transformed into high precision, and that is only possible by exterior (high precision) intervention. 

You can think of a radiating body as a choir of crickets of different frequencies, with higher frequencies requiring more coordination/precision of many crickets, in order to be heard over a surrounding lower frequency background noise.

In order for an opera solist to not be drowned by the forte of a big orchestra, high precision 
focussing of the voice is necessary. 

Let us now give some more examples illustrating that transfer from warm to cold is physical/observable while transfer from cold to warm is unphysical/nonobservable, because of limitations in analog finite precision computation:
  • A wise can teach a fool, but a fool cannot teach a wise.
  • Anybody can smash an expensive Chinese vase into pieces, but nobody can reassemble it.
  • A resume of a book can be written by anybody, but a not a book from a resume. 
  • A picture can be blurred by dust, but not unblurred.
  • An expert can see a difference where a non-expert sees nothing. 
  • Correct temperature data can be erased by one click, but cannot be created.
  • One hot expert climate scientist cannot learn anything from the luke-warm consensus of thousands of non-experts. 
  • The cold hearts of many neighbors cannot bring warmth to your own, but the warm heart of one stranger can.
  • The more heated a debate is, the higher can the pitch be.
  • The hotter the jazz is, the quicker is the tempo.
  • The bigger a choir/orchestra is, the more precision of the singers/musicians is required to make good music.
  • Hot scepticism is spreading into cold global warming alarmism.
You can by yourself easily come up with many more examples (because it does not require high precision).

PS You find more material on finite precision computation and its relation to the 2nd Law of Thermodynamics (connected to blackbody radiation), in


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