Talk:Entropy (energy dispersal)

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[edit] Archives

[edit] NPOV

Has nobody noticed that putting a particular theory on a separate page is completely in contradiction to NPOV? The only way to do something of the sort within the rules might be to link to an external source. It is really just the same as Origin of species (Biology) and origin of species (biblical). And the article itself is not exactly encylopedic standards. And, coming from outside a little, perhaps changing this title to entropy (teaching methods) and including several alternate ways of presenting it might solve the problem of how to do it. I understand the difficulty of presenting exact theory in beginning courses, since I have been facing the challenge of presenting entropy to beginning Library & Inf Sci students, totally lacking a scientific background of any sort. (I use analogies.) DGG 05:03, 13 October 2006 (UTC)

Yes – see Talk:Entropy#NPOV .. .dave souza, talk 10:47, 13 October 2006 (UTC)
This change is a work in progress. Entropy is a huge topic; the trend has been to use mini-articles with "links to main" on central page or to use "see also" and then put the rest on a separate page. --Sadi Carnot 12:20, 27 October 2006 (UTC)

[edit] New page cleaning tasks

I have found this "dispersal" perspective used in Starr's Biology - the Unity and Diversity of Life textbook (1992), 6th Ed. and Atkins book The Second Law (1984). Either Atkins is the primary source of this perspective or there is someone else who started this concept; in either case it would be good to find the correct historical basis for this idea. I am going to make a short header article on the entropy page with a link to main.

One issue we will have to correct on this page is the book list. I have Ebbing's General Chemistry 3rd Ed. (1990) and Brown's Chemistry - the Central Science 9th Ed. (2003) and they both use the disorder perspective. I am going to assume that the newer additions use the dispersal perspective? Yet, I question this because I also have Sagan's book Into the Cool (2005) and it does talk about Frank L. Lambert (pgs. 82-84), but these four pages devoted to Lambert's ideas (out of 267 other authors cited in the book) talk about chemical kinetics, Murphy's law, and activation energy not about "energy dispersal"? This leads me to question the entire list on this page that was submitted by Frank Lambert; maybe it is just a list of books that mentions his work, but not necessarily energy dispersal? I will remove Sagan's book for now and we will have to clean the rest of the list to so to include only those books that mention energy dispersal specifically and cite the actual pages and reference sentences directly. Perhaps Lambert can aid in this task? I also don't like the words "teaching approach"...it doesn't make any sense. --Sadi Carnot 12:12, 27 October 2006 (UTC)

[edit] Poor Boltzmann

Can pls somebody give a specific reference where Boltzmann used the term "Unordnung" (disorder). I don't have the complete works at hand but only the selected works in Ostwalds Klassiker der exakten Wissenschaften Band 286, and I can't find it used. IMHO it's also completely out of his usual diction. Most often he is using "Permutabilzätsmaß", i.e. the number of microstates. --Pjacobi 17:21, 1 November 2006 (UTC)

Boltzmann used the term molar-ordered and molar-disordered (pg. 40) in his Gas Lectures (Dover reprint). Also, I know that Helmholtz used the term in 1882, i.e. from entropy (order and disorder), in 1882 Hermann von Helmholtz used the word "Unordnung" (disorder) to describe entropy.[1]
  1. ^ Anderson, Greg (2005). Thermodynamics of Natural Systems. Cambridge University Press. ISBN 0521847729. 
Later: --Sadi Carnot 04:50, 7 November 2006 (UTC)


Sadi, since you were thoughtful to mirror the Archives pertinent to Pjacobi's question, I thought you would include a lead to my extended discussion of Boltzmann and his innocent use of 'disorder' -- in the sense that he was speaking prior to detailed knowledge of molecular behavior, before quantization of energy, before the third law, and without knowledge of the "Boltzmann entropy equation". Thus came his unfortunate simplistic statement that then shaped conceptual thought for over a century -- on p. 443 after more than 400 pages (US translation) of still-powerful theory. Here's the lead: http://en.wikipedia.org/wiki/Talk:Entropy/Archive2#Disorder, and here's the seminal paragraph:

“In order to explain the fact that the calculations based on this assumption correspond to actually observable processes, one must assume that an enormously complicated mechanical system represents a good picture of the world, and that all or at least most of the parts of it surrounding us are initially in a very ordered – and therefore very improbable – state. When this is the case, then whenever two of more small parts of it come into interaction with each other the system formed by these parts is also initially in an ordered state and when left to itself it rapidly proceeds to the disordered most probable state.” (Final paragraph of #87, p. 443.)
'Order to disorder' -- on this slight basis of "If the result is 'disordered', the initial state must have been 'ordered'". Even a genius can err if he does not have adequate data. FrankLambert 05:09, 9 November 2006 (UTC)
Yes, thank you Frank, this is a good section; I'll add it to entropy (order and disorder). However, "theories on molecular behavior" go back farther than Boltzmann. In 1859, for example, Maxwell was writing about "variations in the velocities of atoms and molecules". In 1862, Clausius was speaking of "changes in the arrangements of the molecules" in terms of molecular disgregation. See also: History of the molecule (an article I recently wrote). Later: --Sadi Carnot 19:16, 13 November 2006 (UTC)

[edit] Student point of view

User:Dave souza keeps writing stuff in this article using the word "student" all over the place. This, by far, is not in line with WP:NPOV. Moreover, since this whole dispersal debate began, I have read several of the historical books on this dispersal approach, and they do not repeat the word "student" all over the place. Souza is obviously greatly influenced by Frank L. Lambert's websites. Wikipedia is supposed to be written so to be available to a world audience of all ages. I would suggest he clean this article accordingly. --Sadi Carnot 05:02, 7 November 2006 (UTC)

Good point, thanks for picking this up. As suggested, I've copyedited the article to make it more general and in line with the historical background now shown. .. dave souza, talk 09:47, 9 November 2006 (UTC)
Looks better, good work. I've found that the English chemical engineer Kenneth Denbigh, in his 1955 textbook The Principles of Chemical Equilibrium, was the first to use the spreading and sharing of energy approach to entropy (although he doesn't use the word "dispersal" per se). Later: --Sadi Carnot 19:34, 13 November 2006 (UTC)

[edit] "The world audience of all ages ..."

This concept of the audience is central to the whole concept of Wikipedia. We must be wary of it being dominated by academics of the wrong kind.

The article says in a condescending way - "By giving concrete examples, this approach is effective in explaining entropy to assist those who have great difficulty in grasping mathematical abstractions."

I would supplement this comment with - "Those who have a grasp of the mathematical abstraction and have no idea of (or don't care about) the concrete examples really have no understanding at all."

People such as Galileo, Newton, Kelvin, Maxwell, Einstein and so on were well aware of their concrete examples and followed up with the mathematical analysis. Read them and you will see what I mean.

Anyone who proclaims "I can follow the maths therefore I know all about it so I need know nothing of concrete examples" are fakes. They give academics a bad name. —The preceding unsigned comment was added by 203.9.185.137 (talk) 03:40, 23 February 2007 (UTC).