Avoiding a Divide by Zero with Absolute Entropy

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I've been reading that unlike enthalpy, entropy has an absolute value that we obtain by setting it equal to zero at absolute zero temperature, but I'm having a hard time understanding how to avoid a divide-by-zero when actually calculating it. I'm thinking that if you wanted to calculate the absolute entropy of an ideal gas, you'd start at absolute zero with zero entropy, then heat it up at constant volume using ΔS=cvlnT2T1ΔS=cvln⁡T2T1 After that, you could isothermally expand it to whatever state you want, but if we're starting at absolute zero, then T1T1 is 0K. Am I making some kind of mistake somewhere? Thanks. thermodynamics entropy physical-chemistry shareciteimprove this question asked Jul 14 at 1:40 John Stanford 475

3   Yes, the mistake is that you assumed the heat capacity cvcv was constant. In reality, the very observation you just made, along with the fact that entropy should be finite at absolute zero, tells us that cvcv must vanish as TT goes to zero. This is called the Third Law of Thermodynamics. – knzhou Jul 14 at 1:51 1   From Quantum Statistics one can show that the specific heat goes to zero as a power law of the temperature. – Diracology Jul 14 at 2:18 add a comment

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I think your mistake comes from assuming that there is an absolute zero temperature. Your formula should be corrected as below: ΔS=limT1→0∫T2T1cv(T)dTTΔS=limT1→0∫T1T2cv(T)dTT And as it is said in comments this is not a divided by zero. This includes an indeterminate form. Because when T1→0T1→0, cv(T)→0cv(T)→0. shareciteimprove this answer answered Jul 14 at 3:15 lucas 2,0262736

Thanks! That makes sense, but how do you calculate absolute entropy if you don't do it that way? I thought about trying to calculate it from the enthalpy and Gibbs free energy of formation but that gave a negative number for water vapor, which doesn't make sense. – John Stanford Jul 14 at 3:31  G=H−TSG=H−TS, (-228.6 kJ/mol)=(-241.82 kJ/mol) - (298K)S gives S = -0.044 kJ/mol – John Stanford Jul 14 at 3:35  What I'm ultimately trying to do is write some code that calculates the Gibbs free energy for any ideal gas given the necessary thermodynamic properties and state information, but even if there's a way to bypass the need to calculate absolute entropy, I'm still curious to know how to do it for it's own sake. – John Stanford Jul 14 at 3:41  @JohnStanford Sorry, sufficient discussion about absolute entropy (entropy with respect to entropy at zero temperature) needs to use quantum theories in statistical mechanics and I have no expertness in that topic. I hope there will be more posted answers by competent users. – lucas Jul 14 at 4:26  @JohnStanford In addition, as far as I know all existent tables include the amounts of properties with respect to a conventional state. – lucas Jul 14 at 4:29 https://physics.stackexchange.com/questions/267948/avoiding-a- divide-by-zero-with-absolute-entropy 熱力学とゼロ除算 \documentclass[12pt]{article} \usepackage{latexsym,amsmath,amssymb,amsfonts,amstext,amsthm} \numberwithin{equation}{section} \begin{document} \title{\bf  Announcement 326:   The division by zero z/0=0 - its impact to human beings through education and research\\ (2016.10.17)} \author{{\it Institute of Reproducing Kernels}\\ Kawauchi-cho, 5-1648-16,\\ Kiryu 376-0041, Japan\\  } \date{\today} \maketitle {\bf Abstract: } In this announcement, for its importance we would like to state the situation on the division by zero and propose basic new challenges to education and research on our wrong world history. \bigskip \section{Introduction} %\label{sect1} By a {\bf natural extension} of the fractions \begin{equation} \frac{b}{a} \end{equation} for any complex numbers $a$ and $b$, we found the simple and beautiful result, for any complex number $b$ \begin{equation} \frac{b}{0}=0, \end{equation} incidentally in \cite{s} by the Tikhonov regularization for the Hadamard product inversions for matrices and we discussed their properties and gave several physical interpretations on the general fractions in \cite{kmsy} for the  case of real numbers.  The division by zero has a long and mysterious story over the world (see, for example, Google site with the division by zero) with its physical viewpoints since the document of zero in India on AD 628,  however,   Sin-Ei Takahasi (\cite{kmsy}) established a simple and decisive interpretation (1.2) by analyzing the extensions of fractions and by showing the complete characterization for the property (1.2):  \bigskip  {\bf  Proposition 1. }{\it Let F be a function from  ${\bf C }\times {\bf C }$  to ${\bf C }$ satisfying $$ F (b, a)F (c, d)= F (bc, ad) $$ for all $$ a, b, c, d  \in {\bf C } $$ and $$ F (b, a) = \frac {b}{a },  \quad   a, b  \in  {\bf C }, a \ne 0. $$ Then, we obtain, for any $b \in {\bf C } $ $$ F (b, 0) = 0. $$ }  Note that the complete proof of this proposition is simply given by  2 or 3 lines. We should define $F(b,0)= b/0 =0$, in general. \medskip We thus should consider, for any complex number $b$, as  (1.2); that is, for the mapping \begin{equation} W = \frac{1}{z}, \end{equation} the image of $z=0$ is $W=0$ ({\bf should be defined}). This fact seems to be a curious one in connection with our well-established popular image for the  point at infinity on the Riemann sphere. Therefore, the division by zero will give great impact to complex analysis and to our ideas for the space and universe. However, the division by zero (1.2) is now clear, indeed, for the introduction of (1.2), we have several independent approaches as in: \medskip 1) by the generalization of the fractions by the Tikhonov regularization and by the Moore-Penrose generalized inverse, \medskip 2) by the intuitive meaning of the fractions (division) by H. Michiwaki - repeated subtraction method, \medskip 3) by the unique extension of the fractions by S. Takahasi,   as in the above, \medskip 4) by the extension of the fundamental function $W = 1/z$ from ${\bf C} \setminus \{0\}$ into ${\bf C}$ such that $W =1/z$ is a one to one and onto mapping from $ {\bf C} \setminus \{0\} $ onto ${\bf C} \setminus \{0\}$ and the division by zero $1/0=0$ is a one to one and onto mapping extension of the function $W =1/z $ from  ${\bf C}$ onto ${\bf C}$, \medskip and \medskip 5) by considering the values of functions with the mean values of functions. \medskip Furthermore, in (\cite{msy}) we gave the results in order to show the reality of the division by zero in our world: \medskip \medskip A) a field structure  containing the division by zero --- the Yamada field ${\bf Y}$, \medskip B)  by the gradient of the $y$ axis on the $(x,y)$ plane --- $\tan \frac{\pi}{2} =0$, \medskip C) by the reflection $W =1/\overline{z}$ of $W= z$ with respect to the unit circle with center at the origin on the complex $z$ plane --- the reflection point of zero is zero, not the point at infinity. \medskip and \medskip D) by considering rotation of a right circular cone having some very interesting phenomenon  from some practical and physical problem. \medskip In (\cite{mos}),  many division by zero results in Euclidean spaces are given and  the basic idea at the point at infinity should be changed. In (\cite{ms}), we gave beautiful geometrical interpretations of determinants from the viewpoint of the division by zero. The results show that the division by zero is our basic and elementary mathematics in our world. \medskip See  J. A. Bergstra, Y. Hirshfeld and J. V. Tucker \cite{bht} for the relationship between fields and the division by zero, and the importance of the division by zero for computer science. It seems that the relationship of the division by zero and field structures are abstract in their paper. Meanwhile,  J. P.  Barukcic and I.  Barukcic (\cite{bb}) discussed recently the relation between the divisions $0/0$, $1/0$ and special relative theory of Einstein. However, their logic seems to be curious and their results contradict with ours.  Furthermore,  T. S. Reis and J.A.D.W. Anderson (\cite{ra,ra2}) extend the system of the real numbers by introducing an ideal number for the division by zero $0/0$.  Meanwhile, we should refer to up-to-date information: {\it Riemann Hypothesis Addendum - Breakthrough Kurt Arbenz https://www.researchgate.net/publication/272022137 Riemann Hypothesis Addendum -   Breakthrough.} \medskip Here, we recall Albert Einstein's words on mathematics: Blackholes are where God divided by zero. I don't believe in mathematics. George Gamow (1904-1968) Russian-born American nuclear physicist and cosmologist remarked that "it is well known to students of high school algebra" that division by zero is not valid; and Einstein admitted it as {\bf the biggest blunder of his life} [1]： 1. Gamow, G., My World Line (Viking, New York). p 44, 1970.  Apparently, the division by zero is a great missing in our mathematics and the result (1.2) is definitely determined as our basic mathematics, as we see from Proposition 1.  Note  its very general assumptions and  many fundamental evidences in our world in (\cite{kmsy,msy,mos}). The results will give great impact  on Euclidean spaces, analytic geometry, calculus, differential equations, complex analysis and  physical problems. The mysterious history of the division by zero over one thousand years is a great shame of  mathematicians and human race on the world history, like the Ptolemaic system (geocentric theory). The division by zero will become a typical  symbol of foolish human race with long and unceasing struggles. Future people will realize this fact as a definite common sense. We should check and fill our mathematics, globally and beautifully, from the viewpoint of the division by zero. Our mathematics will be more perfect and beautiful,  and will give great impact to our basic ideas on the universe.  For our ideas on the division by zero, see the survey style announcements. \section{Basic Materials of Mathematics}   (1): First, we should declare that the divison by zero is possible in the natural and uniquley determined sense and its importance.   (2): In the elementary school, we should introduce the concept of division by the idea of repeated subtraction method by H. Michiwaki whoes method is applied in computer algorithmu and in old days for calculation of division. This method will give a simple and clear method for calculation of division and students will be happy to apply this simple method at the first stage. At this time, they will be able to understand that the division by zero is clear and trivial as $a/0=0$ for any $a$. Note that Michiwaki knows how to apply his method to the complex number field.   (3): For the introduction of the elemetary function $y= 1/x$, we should give the definition of the function at the origin $x=0$ as $y = 0$ by the division by zero idea and we should apply this definition for the occasions of its appearences, step by step, following the curriculum and the results of the division by zero.   (4): For the idea of the Euclidean space (plane), we should introduce, at the first stage, the concept of steleographic projection and the concept of the point at infinity  -    one point compactification. Then, we will be able to see the whole Euclidean plane, however, by the division by zero, the point at infinity is represented by zero. We can teach  the very important fact with many geometric and analytic geometry methods. These topics will give great pleasant feelings to many students.   Interesting topics are: parallel lines, what is a line? - a line contains the origin as an isolated point for the case that the native line does not through the origin. All the lines pass the origin, our space is not the Eulcildean space and is not Aristoteles for the strong discontinuity at the point at infinity (at the origin). - Here note that an orthogonal coordinates should be fixed first for our all arguments. (5): The inversion of the origin with respect to a circle with center the origin is the origin itself, not the point at infinity - the very classical result is wrong. We can also prove this elementary result by many elementary ways. (6): We should change the concept of gradients; on the usual orthogonal coordinates $(x,y)$,  the gradient of the $y$ axis is zero; this is given and proved by the fundamental result  $\tan (\pi/2) =0$. The result is trivial in the definition of the Yamada field. This result is derived also from  the {\bf division by zero calculus}: \medskip  For any formal Laurent expansion around $z=a$, \begin{equation} f(z) = \sum_{n=-\infty}^{\infty} C_n (z - a)^n, \end{equation} we obtain the identity, by the division by zero \begin{equation} f(a) =  C_0. \end{equation} \medskip This fundamental result leads to the important new definition: From the viewpoint of the division by zero, when there exists the limit, at $ x$  \begin{equation}  f^\prime(x) = \lim_{h\to 0} \frac{f(x + h) - f(x)}{h}  =\infty  \end{equation}  or  \begin{equation}  f^\prime(x) =  -\infty,  \end{equation}  both cases, we can write them as follows:  \begin{equation}   f^\prime(x) =  0.  \end{equation}  \medskip  For the elementary ordinary differential equation  \begin{equation}  y^\prime = \frac{dy}{dx} =\frac{1}{x}, \quad x > 0,  \end{equation}  how will be the case at the point $x = 0$? From its general solution, with a general constant $C$  \begin{equation}  y = \log x + C,  \end{equation}  we see that, by the division by zero,  \begin{equation}  y^\prime (0)= \left[ \frac{1}{x}\right]_{x=0} = 0,  \end{equation}  that will mean that the division by zero (1.2) is very natural.  In addition, note that the function $y = \log x$ has infinite order derivatives and all the values are zero at the origin, in the sense of the division by zero.  However, for the derivative of the function $y = \log x$, we have to fix the sense at the origin, clearly, because the function is not differentiable, but it has a singularity at the origin. For $x >0$, there is no problem for (2.6) and (2.7). At  $x = 0$, we  see that we can not consider the limit in the sense (2.3).  However,  for $x >0$ we have (2.6) and  \begin{equation}  \lim_{x \to +0} \left(\log x \right)^\prime = +\infty.  \end{equation}  In the usual sense, the limit is $+\infty$,  but in the present case, in the sense of the division by zero, we have:  \begin{equation}  \left[ \left(\log x \right)^\prime \right]_{x=0}= 0  \end{equation}   and we will be able to understand its sense graphycally.  By the new interpretation for the derivative, we can arrange many formulas for derivatives, by the division by zero. We can modify many formulas and statements in calculus and we can apply our concept to the differential equation theory and the universe in connetion with derivatives. (7): We shall introduce the typical division by zero calculus.   For the integral \begin{equation} \int x(x^{2}+1)^{a}dx=\frac{(x^{2}+1)^{a+1}}{2(a+1)}\quad(a\ne-1), \end{equation} we obtain, by the division by zero, \begin{equation} \int x(x^{2}+1)^{-1}dx=\frac{\log(x^{2}+1)}{2}. \end{equation} We will consider the fundamental ordinary differential equations \begin{equation} x^{\prime \prime}(t) =g -kx^{\prime}(t) \end{equation} with the initial conditions \begin{equation} x(0)  = -h, x^{\prime}(0) =0. \end{equation} Then we have the solution \begin{equation} x(t) = \frac{g}{k}t + \frac{g(e^{-kt}- 1)}{k^2} - h. \end{equation} Then, for $k=0$, we obtain, immediately, by the division by zero \begin{equation} x(t) = \frac{1}{2}g t^2 -h. \end{equation} In those examples, we were able to give valuable functions for denominator zero cases. The division by zero calculus may be applied to many cases as a new fundamental calculus over l'Hôpital's rule. (8):  When we apply the division by zero to functions, we can consider, in general, many ways.  For example, for the function $z/(z-1)$, when we insert $z=1$  in numerator and denominator, we have \begin{equation} \left[\frac{z}{z-1}\right]_{z = 1} = \frac{1}{0} =0. \end{equation} However, from the identity --  the Laurent expansion around $z=1$, \begin{equation} \frac{z}{z-1} = \frac{1}{z-1} + 1, \end{equation} we have \begin{equation}  \left[\frac{z}{z-1}\right]_{z = 1} = 1.  \end{equation}  For analytic functions we can give uniquely determined values at isolated singular points by the values by means of the Laurent expansions as the division by zero calculus, however, the values by means of the Laurent expansions are not always reasonable. We will need to consider many interpretations for reasonable values. In many formulas in mathematics and physics, however, we can see that the division by zero calculus is reasonably valid. See \cite{kmsy,msy}. \section{Albert Einstein's biggest blunder} The division by zero is directly related to the Einstein's theory and various physical problems containing the division by zero.  Now we should check the theory and the problems by the concept of the RIGHT and DEFINITE division by zero. Now is the best time since 100 years from Albert Einstein. It seems that the background knowledge is timely fruitful. Note that the Big Bang also may be related to the division by zero like the blackholes. \section{Computer systems} The above Professors listed are wishing the contributions in order to avoid the division by zero trouble in computers. Now,  we should arrange  new computer systems in order not to meet the division by zero trouble in computer systems.  By the division by zero calculus, we will be able to overcome troubles in Maple for specialization problems. \section{General  ideas on the universe} The division by zero may be related to religion,  philosophy and the ideas on the universe, and it will creat a new world. Look the new world introduced. \bigskip We are standing on a new  generation and in front of the new world, as in the discovery of the Americas.  Should we push the research and education on the division by zero?  \bigskip \bibliographystyle{plain} \begin{thebibliography}{10} \bibitem{bb} J. P.  Barukcic and I.  Barukcic, Anti Aristotle—The Division of Zero by Zero. Journal of Applied Mathematics and Physics,  {\bf 4}(2016), 749-761. doi: 10.4236/jamp.2016.44085. \bibitem{bht} J. A. Bergstra, Y. Hirshfeld and J. V. Tucker, Meadows and the equational specification of division (arXiv:0901.0823v1[math.RA] 7 Jan 2009). \bibitem{cs} L. P.  Castro and S. Saitoh,  Fractional functions and their representations,  Complex Anal. Oper. Theory {\bf7} (2013), no. 4, 1049-1063. \bibitem{kmsy} M. Kuroda, H. Michiwaki, S. Saitoh, and M. Yamane, New meanings of the division by zero and interpretations on $100/0=0$ and on $0/0=0$, Int. J. Appl. Math.  {\bf 27} (2014), no 2, pp. 191-198,  DOI: 10.12732/ijam.v27i2.9. \bibitem{ms} T. Matsuura and S. Saitoh, Matrices and division by zero $z/0=0$, Advances in Linear Algebra \& Matrix Theory, 6, 51-58. http://dx.doi.org/10.4236/alamt.2016.62007 http://www.scirp.org/journal/alamt　 \bibitem{msy} H. Michiwaki, S. Saitoh,  and  M.Yamada, Reality of the division by zero $z/0=0$.  IJAPM  International J. of Applied Physics and Math. {\bf 6}(2015), 1--8. http://www.ijapm.org/show-63-504-1.html \bibitem{mos} H.  Michiwaki, H. Okumura, and S. Saitoh, Division by Zero $z/0 = 0$ in Euclidean Spaces.  International Journal of Mathematics and Computation  (in press). \bibitem{ra} T. S. Reis and J.A.D.W. Anderson, Transdifferential and Transintegral Calculus, Proceedings of the World Congress on Engineering and Computer Science 2014 Vol I WCECS 2014, 22-24 October, 2014, San Francisco, USA \bibitem{ra2} T. S. Reis and J.A.D.W. Anderson, Transreal Calculus, IAENG  International J. of Applied Math., {\bf 45}(2015):  IJAM 45 1 06. \bibitem{s} S. Saitoh, Generalized inversions of Hadamard and tensor products for matrices,  Advances in Linear Algebra \& Matrix Theory.  {\bf 4}  (2014), no. 2,  87--95. http://www.scirp.org/journal/ALAMT/ \bibitem{ttk} S.-E. Takahasi, M. Tsukada and Y. Kobayashi,  Classification of continuous fractional binary operations on the real and complex fields,  Tokyo Journal of Mathematics,   {\bf 38}(2015), no. 2, 369-380. \bibitem{ann179} Announcement 179 (2014.8.30): Division by zero is clear as z/0=0 and it is fundamental in mathematics. \bibitem{ann185} Announcement 185 (2014.10.22): The importance of the division by zero $z/0=0$. \bibitem{ann237} Announcement 237 (2015.6.18):  A reality of the division by zero $z/0=0$ by  geometrical optics. \bibitem{ann246} Announcement 246 (2015.9.17): An interpretation of the division by zero $1/0=0$ by the gradients of lines. \bibitem{ann247} Announcement 247 (2015.9.22): The gradient of y-axis is zero and $\tan (\pi/2) =0$ by the division by zero $1/0=0$. \bibitem{ann250} Announcement 250 (2015.10.20): What are numbers? -  the Yamada field containing the division by zero $z/0=0$. \bibitem{ann252} Announcement 252 (2015.11.1): Circles and curvature - an interpretation by Mr. Hiroshi Michiwaki of the division by zero $r/0 = 0$. \bibitem{ann281} Announcement 281 (2016.2.1): The importance of the division by zero $z/0=0$. \bibitem{ann282} Announcement 282 (2016.2.2): The Division by Zero $z/0=0$ on the Second Birthday. \bibitem{ann293} Announcement 293 (2016.3.27):  Parallel lines on the Euclidean plane from the viewpoint of division by zero 1/0=0. \bibitem{ann300} Announcement 300 (2016.05.22): New challenges on the division by zero z/0=0. \end{thebibliography} \end{document}