Re: [Fis] Re: miscellanea / temperature / symmetry

Message-Id: <5.2.1.1.0.20040422111005.0250c770@mail.iif.hu>
X-Sender: darvasg@mail.iif.hu
X-Mailer: QUALCOMM Windows Eudora Version 5.2.1
Date: Thu, 22 Apr 2004 11:17:56 +0200
To: Michel Petitjean <ptitjean@itodys.jussieu.fr>, <fis@listas.unizar.es>
From: Gyorgy Darvas <darvasg@helka.iif.hu>
Subject: Re: [Fis] Re: miscellanea / temperature / symmetry
In-Reply-To: <200404220856.i3M8uvpO475726@ds10.itodys.jussieu.fr>
Mime-Version: 1.0
Content-Type: text/html; charset="iso-8859-1"
X-Virus-Scanned: TAMIZ + Clamav en unizar.es

Dear Pedro, Michel and the rest of FISers,

(1) everyday perception of temperature and entropy
Yo can give people a simple tool to measure temperature. You cannot do the
same for entropy. This is so simply, why "most will
claim that they know what is temperature, but little people will claim that
they know what is entropy, although both concepts are defined within the
same course of thermodynamics".

(2) concerning the relation of entropy and symmetry (and order!),
please consult my approach, sent to a previous FIS discussion at
http://fis.iguw.tuwien.ac.at/mailings/att-1036/01-Darvas-Wien.ppt

Regards,
Gyuri

At 10:56 2004. 04. 22. +0200, you wrote:
>To: <fis@listas.unizar.es>
>Subj: [Fis] Re: miscellanea / temperature / symmetry
>
>Dear FISers;
>
>Pedro asked a very imprtant question: what are the relationships
>between temperature and entropy.
>I heard about temperature first as a function of pressure and volume
>for gas (equation of state). Then, going further in thermodynamics,
>came thermal equilibrium, heat, thermal exchanges, Carnot engine and
>Carnot cycle. It appears that the definition of temperature and
>the definition of entropy arise both here, and are closely intricated
>(e.g. see the first part of the book of Alberty and Silbey).
>Temperature is related to energy in gas kinetic theory.
>I do not go further because we are now disconnected from "information",
>but I do the following remark:
>Ask to people what is temperature and what is entropy: most will
>claim that they know what is temperature, but little people will
>claim that they know what is entropy, although both concepts
>are defined within the same course of thermodynamics.
>(imagine what would think people if temperatures and entropy values
>appeared together on the TV screen, when the wheather is commented...).
>
>About symmetry and its relations to entropy: symmetry theory and
>entropy (information theory) are both related to distributions.
>But, symmetry theory has to work for distributions, discarding whether
>they are finite discrete, or infinite, or continuous. Informational
>entropy is mainly connected to finite discrete distributions, despite
>some extensions in the continuous case.
>Much more problematic is that the entropy associated to a discrete
>distribution does not care of the numerical values to which non null
>probabilities are attached, and in fact, entropy exists even if the
>probabilities are defined on a non numerical space: e.g.:
>P(red)=1/3, P(green)=1/3, P(blue)=1/3 is a distribution for which
>entropy can be calculated. This is false for symmetry calculations,
>which deals mainly with euclidean multivariate distributions.
>So, entropy and symmetry are quite different. An other question
>is their relations with order and disorder...
>
>This is my 4th message for this week. I will be silent until next week.
>
>Michel Petitjean Email: petitjean@itodys.jussieu.fr
>Editor-in-Chief of Entropy entropy@mdpi.org
>ITODYS (CNRS, UMR 7086) ptitjean@ccr.jussieu.fr
>1 rue Guy de la Brosse Phone: +33 (0)1 44 27 48 57
>75005 Paris, France. FAX : +33 (0)1 44 27 68 14
>http://www.mdpi.net http://www.mdpi.org
>http://petitjeanmichel.free.fr/itoweb.petitjean.html
>http://petitjeanmichel.free.fr/itoweb.petitjean.freeware.html
>_______________________________________________
>fis mailing list
>fis@listas.unizar.es
>http://webmail.unizar.es/mailman/listinfo/fis

Symmetry Festival 2003 http://www.conferences.hu/symmetry2003/
___________________________________________________________________
Gyorgy Darvas darvasg@helka.iif.hu; h492dar@ella.hu
                        http://www.mtakszi.iif.hu/darvas.htm
S Y M M E T R I O N http://us.geocities.com/symmetrion/ [email protected]
Address: c/o MTA KSZI; 18 Nador St., Budapest, H-1051 Hungary
Mailing address: P.O. Box 994, Budapest, H-1245 Hungary
Fax: 36 (1) 331-3161 Phone: 36 (1) 312-3022; 36 (1)
331-3975
___________________________________________________________________

Symmetry Festival 2003 http://www.conferences.hu/symmetry2003/
___________________________________________________________________
Gyorgy Darvas darvasg@helka.iif.hu; h492dar@ella.hu
                        http://www.mtakszi.iif.hu/darvas.htm
S Y M M E T R I O N http://us.geocities.com/symmetrion/ [email protected]
Address: c/o MTA KSZI; 18 Nador St., Budapest, H-1051 Hungary
Mailing address: P.O. Box 994, Budapest, H-1245 Hungary
Fax: 36 (1) 331-3161 Phone: 36 (1) 312-3022; 36 (1)
331-3975
___________________________________________________________________
Received on Thu Apr 22 14:31:30 2004