Subject: Re: CCL:Citation

From: "Jens Spanget-Larsen" <[email-masked]>
Date: Thu, 15 Mar 2001 09:10:32 +0100

Wibke Sudholt:

> could anybody give me - for educational purposes - the sentence Dirac - I
> think - said about that "in principle one can calculate the whole chemistry" -
> if possible in German - and where and when he stated this?

P. A. M. Dirac, Proceedings of the Royal Society of London, Series A, Vol. 
CXXIII, April 1929, pp 714:

"... The underlying physical laws necessary for the mathematical theory of a 
large part of physics and the whole of chemistry are thus completely known, and 
the difficulty is only that the exact application of these laws leads to 
equations much too complicated to be soluble. It therefore becomes desireable 
that approximate practical methods of applying quantum mechanics should be 
developed, which can lead to an explanation of the main features of complex 
atomic systems without too much computation."

Hence, Dirac only stated that "the underlying physical laws ... for the whole 
of chemistry are complete known".  He did NOT claim that all aspects of 
chemistry could be derived from these fundamental laws.  Knowledge of the 
"underlying physical laws" does not, in general, allow us to anticipate all 
aspects of 'reduced' sciences.  More or less like the concept of 'chaos' is not 
easily anticipated solely from a knowledge of Newton's classical mechanics, or 
the phenomenon 'life' is not easily derived from a knowledge of chemistry, and 
so on.

Yours, Jens >--<

=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
JENS SPANGET-LARSEN         Phone: +45 4674 2000 (RUC)
Department of Chemistry            +45 4674 2710 (direct)
Roskilde University (RUC)   Fax:   +45 4674 3011 
P.O.Box 260                 E-Mail: [email-masked]
DK-4000 Roskilde, Denmark   http://virgil.ruc.dk/~jsl/
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=