June 2010 contents 1 introduction 1 2 entropy in thermodynamics 2 3 information theory 4 4 statistical mechanics 9 5 dynamical systems theory 18 6 fractal geometry 26 7 conclusion 30 1 introduction entropy is ubiquitous in physics, and it plays important roles in numerous. If someone points out to you that your pet theory of the universe is in disagreement with maxwells equations then so much the worse for maxwells equations. These fits are used by the chemkin collection, a generalpurpose chemical kinetics software package. Spreadsheet calculations of thermodynamic properties larry caretto, david mcdaniel, tom mincer csu, northridgeus air force academycsu, northridge abstract a thermodynamic property calculation tool has been developed based on the excel spreadsheet program. Pdf entropy is ubiquitous in physics, and it plays important roles in numerous other.
Thermodynamics for cryogenics tom peterson 3 old science with modern applications thermodynamics is the study of macroscopic energy transformations between heat and work thermodynamics has its basis in attempts to understand combustion and steam power much in the 19th century but is still state of the art in terms of practical. Thermodynamic properties a quantity which is either an attribute of an entire system or is a function of position which is continuous and does not vary rapidly over microscopic distances, except possibly for abrupt changes at boundaries between phases of the system. If it is found to be contradicted by observation well. Thermodynamic properties tp thermodynamic properties define and articulate some of the critical language and concepts of thermodynamics distinguish between the universe, system, surroundings, and boundary ch 1. After looking at a variety of examples, one can simply conclude to one fact. I posted a quick enscript yesterday that calculates the entropy of any selected object in encase. Physical properties chemical formula ch 2 f 2 chf 2 cf 3 5050% by weight molecular weight 72. Properties of entropy university of texas at austin. For each state a the negative difference between the entropy of a and the entropy of the maximal state b is nearly proportional to the. In general words, entropy is referred as the measurement of particular data in digital values. Entropy does not do any compression on the data and is thereby completely ignorant of any patterns so 000000111111 has same h and s as 01011110 6 1s and 6 0s in both cases.
Thermal entropy is a property of a thermodynamic system that results from motion of particles. Entropy thomas pynchon 1960 im going to be honest with you. Entropy and information theory first edition, corrected robert m. In sociology, entropy is the natural decay of structures 3. A quantity whose cyclic integral is zero depends on the state only. Lecture notes thermodynamics of biomolecular systems. Entropy and the second law of thermodynamics the second law of thermodynamics in thermochemistry we have seen that reactions are infl uenced by the comparative enthalpies of reactants and products. While both of these examples obey the first law regardless of.
However in the real world, files that contain random data have no utility in a file system, therefore it is highly probable that files with high entropy are actually encrypted or compressed. Ip to have several properties note that along with the axiom is. If you have 2 properties, you can find the others using the thermodynamic property tables. Find materials for this course in the pages linked along the left. Additional equations have been developed for the calculation of saturated liquid enthalpy, latent enthalpy, and saturated liquid entropy and are presented here. Entropy, relative entropy, uncertainty, information theory. If you need an entropy or entropy per byte, to be exact the best way is to compress it using gzip, bz2, rar or any other strong compression, and then divide compressed size by uncompressed size. Calculates and plots isolines of pressure, temperature, specific enthalpy, specific entropy, specific volume and vapor fraction for 4 different plot diagrams.
Pdf entropy a guide for the perplexed researchgate. This tool can be used to determine individual state points by a graphical. Convergence properties of the crossentropy method for discrete optimization andre costa a. Calculate actual property values, by introducing residual properties and. Iapwsif97 thermodynamic and transport properties of steam. In this article i will describe how entropy as a measure of randomness can be used to solve the following gambling problem. Given a combination of two thermodynamic properties out of 14 different possible combinations, it calculates 20 thermodynamic and transport properties of steam and 10 partial derivatives.
Again, we tackled things in very general terms and really only dealt with extremes. Nist chemistry webbook searchable database for thermodynamic and molecular data. This is a fascinating subject, which arose once the notion of information got precise and quantifyable. Similar to this, the term file entropy is the representation of data sets in specific file. Even our mathematical work is registered mainly as computer files. A system is considered homogeneous if all of its properties are uniform at any point. The entropy of a binary hidden markov process or zuk1, ido kanter2 and eytan domany1 1dept. In general you cannot talk about entropy of a given file. The periodic table interface enables downloading tables in printable or tabdelimited text files.
Like energy, information can reside in one place or another, it can be transmitted through space, and it can be stored for later use. Firstly, in the field of information, entropy represents the loss of information of a physical system observed by an outsider, but within the system, entropy represents countable information. Suppose that we choose a new resolution and define a new density of states which is the number of states with. Moreover, it would be unnecessary to do so, because the quantities that are dealt with in thermodynamics are average properties of the. Thermodynamic properties tp thermodynamic properties. Gray information systems laboratory electrical engineering department stanford university. Entropy a guide for the perplexed charlotte werndl. Information entropy is the logbase2 of the number of. The relative entropy is a measure of the distance between two. Data available as text tables, plots and coefficients of shomate.
If you have pressure and temperature for steam, you can find its specific volume, enthalpy, internal energy, and entropy. The chemkin thermodynamic databasethe chemkin thermodynamic database abstractabstract the chemkin thermodynamic database contains polynomial fits to specific heats, standard state enthalpies, and standard state entropies. Entropy properties of entropy entropy, as we have defined it, has some dependence on the resolution to which the energy of macrostates is measured. Annals of mathematics continuity properties of entropy. The storys pessimistic conclusion made it a little difficult for me to linger over though.
Lecture notes section contains the class notes files. Increase in entropy is referred to as entropy production. Convergence properties of the crossentropy method for. Highentropy alloys or heas are metallic alloys composed of at least five chemical elements in equal or near equal atomic percents at. Few structure models of heas is presented on figure 1. Colligative properties the previous lecture was about solutions and whether they would form or not. Shannon introduced the notion of the average mutual information between the two processes. The entropy of a random variable is a measure of the uncertainty of the random variable. Use these relations to derive equations to calculate enthalpy and entropy values from pvt data and heat capacity data. As can be seen in the equation above, for an internally reversible process the cyclic integral of. For files with equal frequency of each symbol this gives sn. For example, if you have some files and desire to calculate the entropy value for that, then it will be. For now, relative entropy can be thought of as a measure of discrepancy between two.
In fact, selecting the proper method for estimating properties is one of the most important steps that will affect the rest of the simulation. Brissaud suggested that entropy could be understood in three aspects 4. That is, the phrase file entropy is used to measure the amount of data which is present in a selected file. Provides pdf files for species in the 4th edition 1998 printonpaper version of the janaf tables. Spreadsheet calculations of thermodynamic properties. Hxy y gives additional info about x when x and y are independent, hx hxy entropy properties han vinck 20. Dp kq, x u2u pulog pu qu e log pu qu 23 note that by property 3, the relative entropy is always greater than or equal to 0, with equality i q p.
Pdf annals of mathematics continuity properties of. Entropy is defined as the nonwork producing form of energy. An introduction to information theory and entropy csustan. Shannon entropy this chapter is a digression in information theory. However, the concept of shanon entropy shares some intuition with boltzmanns. Ludwig boltzmann gave another, probabilistic meaning to entropy. This information is based on values calculated using the nist. Entropy the clausius inequality forms the basis for the definition of a new property called entropy. There are separate property tables for saturated mixtures, subcooled liquids, superheated vapors, and ideal gases. However, if we add energy in the form of heat to the caliper heat the caliper then we intuitively know that the disk will not rotate. Explaining the entropy concept and entropy components chemrxiv. Thermodynamics enthalpy entropy mollier and steam tables i. Thermodynamics the study of the transformations of energy from one form into another. From a physical point of view, information theory has nothing to do with physics.
The bottom line is that entropy change is a measure of reversibility. Entropy a guide for the perplexed roman frigg and charlotte werndl. Imagine you give your memory stick to a colleague who copies a file onto. It is also regarded as the energy that is not available for performing useful work within a certain environment. The many faces of entropy form a cluster of fundamental concepts in numerous areas of the mathematical sciences, including probability, statistics, information theory, and statistical mechanics. Entropy, as we have defined it, has some dependence on the resolution to which the energy of macrostates is measured. As mentioned, entropy values provides a rough estimation of whether the file is encrypted or not. Diversityindex entropy is one of several ways to measure diversity. Thermodynamic and transport properties of carbohydrates. File entropy explained computer forensics, malware. In conventional textbook thermodynamics, entropy is a quantity that. In order for an alloy to be specified as a hea, the concentrations of components must be between 5 and 35 at. Look at chapter two of this pdf file, it has very good detailed. One of the comments i received asked for more information about what entropy is and what do the values represent.
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