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Boltzmann Entropy of Thermodynamics Versus Shannon Entropy of Information Theory

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Boltzmann Entropy of Thermodynamics Versus Shannon Entropy of Information Theory INTERNATIONAL JOURNAL OF MECHANICS Volume 8, 2014 Boltzmann Entropy of Thermodynamics versus Shannon Entropy of Information Theory Siavash H. Sohrab fβ(uβ) = fβ(rβ, uβ, tβ) drβduβ. Each element is composed of Abstract—Some implications of a scale invariant model of an ensemble of small particles called the "atoms" of the field statistical mechanics to Boltzmann entropy in thermodynamics versus and are viewed as point-mass. The most probable element Shannon entropy in information theory are investigated. The (system) velocity of the smaller scale (j) becomes the velocity objective versus subjective nature of entropy as well as the of the atom (element) of the larger scale (j+1). fundamental significance of the choice of Shannon measure K as Following the classical methods [36-41] the invariant Boltzmann constant k is described. In addition, the impact of the ρ results on Nernst-Planck statement of the third law of definition of density β, and velocity of atom uβ, element vβ, thermodynamics is discussed. and system wβ at the scale β are [35, 42] Keywords—Boltzmann entropy of thermodynamic, Shannon = = , u = v ρβ n ββ m m β∫ f β du β β mpβ−1 (1) entropy of information theory, third law of thermodynamics. −1 I. INTRODUCTION = ρ , w = v (2) vβ βm β∫ uu ββ fd β β mpβ+1 TOCHASTIC quantum fields [1-17] and classical S hydrodynamic fields [18-29] viewed as ensembles of Similarly, the invariant definition of the peculiar and diffusion weakly coupled oscillators resulted in the introduction of a velocities are introduced as scale-invariant model of statistical mechanics [30] and its application to the fields of thermodynamics [31], fluid ′ Vβ= u ββ -v , Vβ= v ββ -w (3) mechanics [32-33], statistical mechanics [34], and quantum mechanics [35]. such that In the present study, some implications of the model to ′ the physical foundation of classical and statistical VVβ= β+1 (4) thermodynamics and Boltzmann thermodynamic entropy versus Shannon information entropy are examined. Because UNIVERSE GALACTIC CLUSTER LGD (J + 11/2) languages involve distinguishable atoms i.e. alphabets, a EGD (J +5) GALACTIC CLUSTER model of language as multicomponent thermodynamic mixture Lg GALAXY Lp LPD (J + 9/2) EPD (J+4 ) GALAXY is examined thus revealing the connections between Shannon Lp PLANET LHD (J + 7/2) Lh information entropy on the one hand and entropy of ideal gas EHD (J +3) PLANET Lh HYDRO-SYSTEM LFD (J + 5/2) mixtures on the other hand. Finally, some of the implications Lf EFD (J +2) Lf HYDRO-SYSTEM of the results to Nernst-Planck statement of the third law of FLUID ELEMENT LED (J + 3/2) Le EED (J+1) thermodynamics are discussed. Le FLUID ELEMENT EDDY Lc LCD (J + 1/2) ECD (J) Lc EDDY II. A SCALE-INVARIANT MODEL OF STATISTICAL MECHANICS CLUSTER Lm LMD (J - 1/2) EMD (J -1) Lm CLUSTER The scale-invariant model of statistical mechanics for MOLECULE La LAD (J - 3/2) equilibrium galactic-, planetary-, hydro-system-, fluid-element- EAD (J -2) La MOLECULE ATOM Ls LSD (J - 5/2) , eddy-, cluster-, molecular-, atomic-, subatomic-, kromo-, and ESD (J -3) Ls ATOM β = SUB-PARTICLE Lk LKD (J - 7/2) tachyon-dynamics corresponding to the scale g, p, h, f, e, EKD (J-4 ) L k SUB-PARTICLE PHOTON c, m, a, s, k, and t is schematically shown in Fig.1 [31]. Each Lt LTD (J - 9/2) ETD (J -5) Lt statistical field is identified as the "system" and is composed of TACHYON PHOTON an ensemble of "elements" described by a distribution function Fig. 1 A scale invariant view of statistical mechanics from cosmic to tachyon scales. This work was supported in part by NASA grant no. NAG3-1863. S. H. Sohrab is with the Department of Mechanical Engineering, When the model is applied to social structures one Northwestern University, Evanston, IL 60208 USA. (phone: 847-491-3572; fax: 847-491-3915; e-mail: s-sohrab@ northwestern.edu). arrives at the cascade shown in Fig. 2. Interestingly, as signs for capacity of number of people in elevators in Athens show, ISSN: 1998-4448 73 INTERNATIONAL JOURNAL OF MECHANICS Volume 8, 2014 in Greek a person is referred to as “atom” that is the smallest ε =mu 〈2 〉 = p 〈λ2 〉 1/2 〈ν 2 〉 1/2 =h ν (6a) unit of social structure shown in Fig. 2. The correspondence β β β β β β ββ between statistical fields in Figs. 1-2 clearly show the physical 2 2 1/2 2 1/2 and objective basis of information and its communication εβ =mu β 〈 β 〉 = p β 〈ν β 〉 〈λ β 〉 =k ββ λ (6b) between “atoms” or individuals be it in the form of particle exchange or exchange of more complex symbols such as when the definition of stochastic Planck and Boltzmann words or numbers. In this sense, the information theory like all factors are introduced as [33] other branches of science must of course be a subset of the theory of everything TOE (Fig. 1). 2 1/2 hpβ= ββ 〈λ 〉 (7a) UNIVERSE SUPER CLUSTER 2 1/2 CLUSTER OF GALAXIES kpβ= ββ 〈ν 〉 (7b) GAL AXY SOLAR SYSTEM At the important scale of EKD (Fig. 1) corresponding to PLANET CLUSTER Casimir [44] vacuum composed of photon gas, the universal constants of Planck [45, 46] and Boltzmann [31] are identified PLANET from equations (6)-(7) as COUNTRY 2 1/ 2 −34 STATE h= hk = m kk c 〈λ 〉 = 6.626 × 10 J-s (8a) COUNTY 2 1/ 2 −23 CITY k= kk = m kk c 〈ν 〉 = 1.381 × 10 J/K (8b) FAMILY Next, following de Broglie hypothesis for the wavelength of PERSON matter waves [2] Fig. 2 Hierarchy of social structures from cosmic to individual or λ=ββh/p (9a) atomic scales. the frequency of matter waves is defined as [31] In examining the small-scale limit of the hierarchy in Fig.2, one notes that a living person is composed of a ν= (9b) collection of living organs. Similarly, a living organ is ββk/p composed of a collection of living cells. Therefore it is interesting to speculate if parallel to Leibnitz monad there When matter and radiation are in the state of thermodynamic exist such a thing as the smallest unit or “atom” of life out of equilibrium equations (9a) and (9b) can be expressed as which all living organisms are constructed. In other words, if all living systems are composed of living elements, is there a hhhβ =k = , kkkβ =k = (10) limit to such an infinite regression. The definitions in equations (8a) and (8b) result in the III. STOCHASTIC NATURES OF PLANCK AND BOLTZMANN gravitational mass of photon [31] CONSTANTS AND DE PRETTO NUMBER 8338 Because at thermodynamic equilibrium the mean velocity of 3 1/ 2 −41 m= (hk / c ) = 1.84278 × 10 kg (12) each particle, Heisenberg-Kramers virtual oscillator [43], k vanishes <uβ> = 0 the translational kinetic energy of particle − oscillating in two directions (x+, x−) is expressed as that is much larger than the reported [47] value of 4× 10 51 kg. The finite gravitational mass of photons was anticipated by 22 Newton [48] and is in accordance with Einstein-de Broglie ε=βm β 〈 u β+ 〉 /2 + mβ 〈 u β− 〉 /2 xx theory of light [49-53]. Avogardo-Loschmidt number was 2 2 1/2 2 1/2 =muβ 〈 β+x 〉 = p β 〈λ β 〉 〈ν β 〉 (5) predicted as [31] o 2 23 2 1/2 N= 1/(mk c ) = 6.0376 × 10 (13) where pβ=〈〉 mu β β+x is the root-mean-square momentum 2 2 of particle and <u β +> = <u β −> by Boltzmann equipartition x x leading to the modified value of the universal gas constant principle. At any scale β, the result in (5) can be expressed in terms of either frequency or wavelength oo R =N k = 8.338 kJ/(kmol-K) (14) ISSN: 1998-4448 74 INTERNATIONAL JOURNAL OF MECHANICS Volume 8, 2014 Also, by (13) the atomic mass unit becomes According to (15) the atomic mass mˆ j of any chemical 2 element j is the product of an integral number representing its amu= mk c molecular weight nj and the universal constant called atomic 1/2 −27 =(hkc) = 1.6563 × 10 kg/kmol (15) mass unit defined in (15) such that 2 mˆ ≈==n (amu) n m c n hkc in harmony with the Since all baryonic matter is known to be composed of atoms, j j jk j equations (12) and (15) suggest that all matter in the universe perceptions of Sommerfeld [61] is composed of light [54]. From (8a)-(8b) the wavelength and 2 1/2 2 1/2 "Our spectral series, dominated as they are by integral quantum frequency of photon in vacuum 〈λ 〉 〈ν 〉 = are kk c numbers, correspond, in a sense, to the ancient triad of the lyre, from which the Pythagoreans 2500 years ago inferred the λ = 〈λ2 〉 1/2 =1/ R o = 0.119935 m , harmony of the natural phenomena; and our quanta remind us of kk the role which the Pythagorean doctrine seems to have ascribed to ν = 〈ν2 〉 1/2 =2.49969 × 109 Hz (16) the integers, not merely as attributes, but as the real essence of kk physical phenomena." In a recent study [35] a modified definition of as well as the ideas of Weyl [62]. thermodynamic temperature T′ = 2T was introduced that resulted in the modified value of Joule-Mayer mechanical IV. OBJECTIVE VERSUS SUBJECTIVE NATURE OF equivalent of heat J [35] THERMODYNAMIC ENTROPY Possible subjective versus objective nature of entropy ==×= J 2Jc 2 4.169 8338 Joule/kcal (17) has been subject of much debate ever since 1948 when Shannon [63-64] used the name entropy in his information theory.
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