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Dec 1999

Volume 67, Issue 12, pp. 1043-1288

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Thermal and statistical physics—from the theme issue editors

Harvey Gould and Jan Tobochnik

American Journal of Physics -- December 1999 -- Volume 67, Issue 12, pp. 1043 | Cited 1 time

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Abstract Unavailable
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01.40.G- Curricula and evaluation
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Bringing atoms into first-year physics

Ruth W. Chabay and Bruce A. Sherwood

American Journal of Physics -- December 1999 -- Volume 67, Issue 12, pp. 1045 | Cited 23 times

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We argue that thermal physics should not be treated as a separate topic in introductory physics. The first-year calculus-based college physics should offer a modern, unified view of physics representative of the contemporary scientific enterprise. It should focus on the consequences of the central fact that matter is composed of atoms, and on the process of modeling physical systems. Such a focus is more interesting and relevant to students than a repetition of a purely classical treatment. We give an example of a course that emphasizes physical modeling of phenomena in terms of the atomic nature of matter. Thermal physics is woven into the entire course and is fully integrated with classical and semiclassical mechanics. © 1999 American Association of Physics Teachers.
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01.50.-i Educational aids
45.05.+x General theory of classical mechanics of discrete systems
45.10.-b Computational methods in classical mechanics
05.20.Dd Kinetic theory

Thermal physics in the introductory physics course: Why and how to teach it from a unified atomic perspective

Frederick Reif

American Journal of Physics -- December 1999 -- Volume 67, Issue 12, pp. 1051 | Cited 14 times

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Heat and thermodynamics are traditionally taught in the introductory physics course from a predominantly macroscopic point of view. However, it is advantageous to adopt a more modern approach that systematically builds on students’ knowledge of the atomic structure of matter and of elementary mechanics. By focusing on the essential physics without requiring more than elementary classical mechanics, this approach can be made sufficiently simple to be readily teachable during five or six weeks of an ordinary calculus-based introductory physics course. This approach can be highly unified, using atomic considerations to infer the properties of macroscopic systems while also enabling thermodynamic analyses independent of specific atomic models. Furthermore, this integrated point of view provides a deeper physical understanding of basic concepts (such as internal energy, heat, entropy, and absolute temperature) and of important phenomena (such as equilibrium, fluctuations, and irreversibility). © 1999 American Association of Physics Teachers.
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01.50.-i Educational aids
05.70.-a Thermodynamics

Development of energy concepts in introductory physics courses

Arnold B. Arons

American Journal of Physics -- December 1999 -- Volume 67, Issue 12, pp. 1063 | Cited 23 times

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The work-energy theorem, derived from Newton’s second law, applies to the displacement of a particle or the center of mass of an extended body treated as a particle. Because work, as a quantity of energy transferred in accordance with the First Law of Thermodynamics, cannot be calculated in general as an applied force times the displacement of center of mass, the work-energy theorem is not a valid statement about energy transformations when work is done against a frictional force or actions on or by deformable bodies. To use work in conservation of energy calculations, work must be calculated as the sum of the products of forces and their corresponding displacements at locations where the forces are applied at the periphery of the system under consideration. Failure to make this conceptual distinction results in various errors and misleading statements widely prevalent in textbooks, thus reinforcing confusion about energy transformations associated with the action in everyday experience of zero-work forces such as those present in walking, running, jumping, or accelerating a car. Without a thermodynamically valid definition of work, it is also impossible to give a correct description of the connection between mechanical and thermal energy changes and of dissipative effects. The situation can be simply corrected and student understanding of the energy concepts greatly enhanced by introducing and using the concept of internal energy, that is, articulating the First Law of Thermodynamics in a simple, phenomenological form without unnecessary mathematical encumbrances. © 1999 American Association of Physics Teachers.
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01.50.-i Educational aids
01.40.Di Course design and evaluation
05.70.-a Thermodynamics

Entropy and time

Vinay Ambegaokar and Aashish A. Clerk

American Journal of Physics -- December 1999 -- Volume 67, Issue 12, pp. 1068 | Cited 8 times

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The emergence of a direction of time in statistical mechanics from an underlying time-reversal-invariant dynamics is explained by examining a simple model. The manner in which time-reversal symmetry is preserved and the role of initial conditions are emphasized. An extension of the model to finite temperatures also is discussed. © 1999 American Association of Physics Teachers.
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01.50.-i Educational aids
05.70.Ce Thermodynamic functions and equations of state
05.20.-y Classical statistical mechanics

Entropy, information, and computation

J. Machta

American Journal of Physics -- December 1999 -- Volume 67, Issue 12, pp. 1074 | Cited 3 times

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The relation between entropy, information, and randomness is discussed. Algorithmic information theory is introduced and used to provide a fundamental definition of entropy. The relation between algorithmic entropy and the usual Shannon–Gibbs entropy is discussed. © 1999 American Association of Physics Teachers.
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01.50.-i Educational aids
05.70.Ce Thermodynamic functions and equations of state
02.50.-r Probability theory, stochastic processes, and statistics
05.40.-a Fluctuation phenomena, random processes, noise, and Brownian motion

Incomplete descriptions and relevant entropies

Roger Balian

American Journal of Physics -- December 1999 -- Volume 67, Issue 12, pp. 1078 | Cited 11 times

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Statistical mechanics relies on the complete although probabilistic description of a system in terms of all its microscopic variables. Its object is to derive from this microscopic description the static and dynamic properties for some reduced set of variables. The elimination of the irrelevant variables is guided by the maximum entropy criterion, which produces the least biased probability law consistent with the available information about the relevant variables. This approach defines relevant entropies which measure the missing information associated with the variables retained in the incomplete description. The relevant entropies depend not only on the state, but also on the coarseness of the reduced description of the system. Their use sheds light on questions such as the second law, both in equilibrium and in irreversible thermodynamics, the projection operator method of statistical mechanics, Boltzmann’s H-theorem, and spin-echo experiments. © 1999 American Association of Physics Teachers.
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01.50.-i Educational aids
05.20.-y Classical statistical mechanics
05.70.Ce Thermodynamic functions and equations of state
02.50.Cw Probability theory
05.70.Ln Nonequilibrium and irreversible thermodynamics

An invertibility paradox

P.-M. Binder, J. M. Pedraza, and S. Garzón

American Journal of Physics -- December 1999 -- Volume 67, Issue 12, pp. 1091 | Cited 2 times

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The chaotic volume-preserving standard map is used to illustrate the invertibility paradox, which is related to the reversibility paradox of the microscopic foundations of thermodynamics. The new paradox, whose resolution relies exclusively on phase-space arguments, gives insight into Boltzmann’s original resolution of the reversibility paradox. © 1999 American Association of Physics Teachers.
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01.50.-i Educational aids
05.70.-a Thermodynamics
05.45.-a Nonlinear dynamics and chaos

A thermodynamic derivative means an experiment

Daniel F. Styer

American Journal of Physics -- December 1999 -- Volume 67, Issue 12, pp. 1094

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All too often, courses in thermodynamics and statistical mechanics barrage their students with numerous equations that are left unexamined and uninvestigated. This note explains how to pause, examine a thermodynamic equation, and render it more meaningful. Three techniques are discussed: (1) design two experiments that would measure the quantities on either side of the equality; (2) examine special cases; (3) consider the consequences if the equality failed to hold. © 1999 American Association of Physics Teachers.
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01.50.-i Educational aids
01.50.Qb Laboratory course design, organization, and evaluation
05.70.-a Thermodynamics
05.20.-y Classical statistical mechanics

Thermodynamics of mixtures: Functions of mixing and excess functions

R. Nieto, M. C. González, and F. Herrero

American Journal of Physics -- December 1999 -- Volume 67, Issue 12, pp. 1096 | Cited 1 time

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Applying thermodynamics to realistic systems requires a knowledge of the thermodynamic properties of mixtures. Functions of mixing and excess functions provide a useful approach. The concepts are simple and their application straightforward, but students often fail to apply them correctly when they are given only a theoretical explanation. We discuss some typical mistakes and some problems we have found useful for overcoming them. © 1999 American Association of Physics Teachers.
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01.50.-i Educational aids
05.70.Ce Thermodynamic functions and equations of state
05.20.-y Classical statistical mechanics
64.75.-g Phase equilibria

Thermodynamics at work: The pressure derivative of the specific heat

J. Güémez, C. Fiolhais, and M. Fiolhais

American Journal of Physics -- December 1999 -- Volume 67, Issue 12, pp. 1100 | Cited 2 times

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Thermodynamics relates measurable quantities such as thermal coefficients and specific heats. The first law, which implies that the enthalpy is a function of state, yields a relation for the pressure derivative of the specific heat cP. The second law gives a simpler and well-known relation for this pressure derivative. We compare the values of the pressure derivative of cP obtained from the first and second laws to the values obtained from measurements for water at different pressures. The comparison illustrates the scope and methodology of thermodynamics. © 1999 American Association of Physics Teachers.
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01.50.-i Educational aids
05.70.Ce Thermodynamic functions and equations of state

Thermodynamics of high temperature, Mie–Gruneisen solids

Don S. Lemons and Carl M. Lund

American Journal of Physics -- December 1999 -- Volume 67, Issue 12, pp. 1105 | Cited 3 times

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We construct a set of equations of state for condensed matter at temperatures well above the Debye temperature. These equations incorporate the Mie–Gruneisen equation of state and generic properties of high temperature solids. They are simple enough to provide an alternative to the ideal gas and the van der Waals equations of state for illustrating thermodynamic concepts. © 1999 American Association of Physics Teachers.
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01.50.-i Educational aids
64.10.+h General theory of equations of state and phase equilibria

A simple demonstration of a metastable state

Narayanan Menon

American Journal of Physics -- December 1999 -- Volume 67, Issue 12, pp. 1109 | Cited 3 times

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A system whose macroscopic properties appear to be unchanging in time may not be in a state of minimum free energy. A common example of such a metastable state is a supercooled liquid. Liquid sodium acetate is a system in which the passage of a supercooled liquid into its stable, crystalline form is readily demonstrated. © 1999 American Association of Physics Teachers.
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01.50.My Demonstration experiments and apparatus
01.50.Pa Laboratory experiments and apparatus
65.20.-w Thermal properties of liquids
65.40.gd Entropy
64.60.Q- Nucleation
64.60.My Metastable phases
64.70.D- Solid-liquid transitions
82.60.Nh Thermodynamics of nucleation
82.60.Cx Enthalpies of combustion, reaction, and formation
82.60.Fa Heat capacities and heats of phase transitions

The thermodynamic cube: A mnemonic and learning device for students of classical thermodynamics

Stephen F. Pate

American Journal of Physics -- December 1999 -- Volume 67, Issue 12, pp. 1111 | Cited 2 times

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The “thermodynamic cube,” a mnemonic device for learning and recalling thermodynamic relations, is introduced. The cube is an extension of the familiar “thermodynamic square” seen in many textbooks. The cube reproduces the functions of the usual thermodynamic squares and incorporates the Euler relations which are not as well known. © 1999 American Association of Physics Teachers.
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01.50.-i Educational aids
05.70.-a Thermodynamics
05.70.Ce Thermodynamic functions and equations of state

What if entropy were dimensionless?

Harvey S. Leff

American Journal of Physics -- December 1999 -- Volume 67, Issue 12, pp. 1114 | Cited 8 times

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One of entropy’s puzzling aspects is its dimensions of energy/temperature. A review of thermodynamics and statistical mechanics leads to six conclusions: (1) Entropy’s dimensions are linked to the definition of the Kelvin temperature scale. (2) Entropy can be defined to be dimensionless when temperature T is defined as an energy (dubbed tempergy). (3) Dimensionless entropy per particle typically is between 0 and ∼80. Its value facilitates comparisons among materials and estimates of the number of accessible states. (4) Using dimensionless entropy and tempergy, Boltzmann’s constant k is unnecessary. (5) Tempergy, kT, does not generally represent a stored system energy. (6) When the (extensive) heat capacity C≫k, tempergy is the energy transfer required to increase the dimensionless entropy by unity. © 1999 American Association of Physics Teachers.
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01.50.-i Educational aids
05.70.-a Thermodynamics
65.20.-w Thermal properties of liquids
65.40.gd Entropy

The art of statistical mechanics: Looking at microscopic spectra and seeing macroscopic phenomena

Jeffrey J. Prentis and Timur Zainiev

American Journal of Physics -- December 1999 -- Volume 67, Issue 12, pp. 1123 | Cited 1 time

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Simple graphical spectra are presented as visual paradigms for the basic ideas of statistical mechanics. Each spectrum is designed so that the mechanical information can be readily converted into thermal and statistical properties. © 1999 American Association of Physics Teachers.
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01.50.-i Educational aids
05.20.-y Classical statistical mechanics
05.70.Ce Thermodynamic functions and equations of state

An experiment to demonstrate the canonical distribution

M. D. Sturge and Song Bac Toh

American Journal of Physics -- December 1999 -- Volume 67, Issue 12, pp. 1129 | Cited 3 times

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We describe a simple experiment, suitable for an undergraduate laboratory, in which the collector current in a transistor is measured as a function of the base–emitter voltage at various temperatures. The experiment gives a very convincing demonstration of the canonical distribution of statistical mechanics, in which the probability of occupancy of a state of energy E is proportional to e−E/kT. © 1999 American Association of Physics Teachers.
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01.50.My Demonstration experiments and apparatus
05.20.-y Classical statistical mechanics
05.70.-a Thermodynamics

Detailed balance, quantum distribution functions, and equilibrium of mixtures

W. E. Lawrence

American Journal of Physics -- December 1999 -- Volume 67, Issue 12, pp. 1132 | Cited 1 time

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We consider systems of nearly free particles (or quasiparticles) interacting by scattering, emission and absorption of radiation, or by physical or chemical transformation. The condition of detailed balance yields the appropriate distribution function for each species, the equality of their temperatures, and a relation for their chemical potentials associated with particle transformations. For example, antiparticles coexisting in equilibrium have opposite chemical potentials, and excitations above the Bose–Einstein condensate have zero chemical potential. For mixtures of classical ideal gases, the law of mass action is obtained. © 1999 American Association of Physics Teachers.
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01.50.-i Educational aids
05.30.Jp Boson systems
05.30.Fk Fermion systems and electron gas
31.15.xm Quasiparticle methods

Three interesting problems in statistical mechanics

Claude Garrod and Mitja Rosina

American Journal of Physics -- December 1999 -- Volume 67, Issue 12, pp. 1140

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Abstract Unavailable
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01.50.-i Educational aids
05.20.-y Classical statistical mechanics

A walk in phase space: Solidification into crystalline and amorphous states

Joan Adler

American Journal of Physics -- December 1999 -- Volume 67, Issue 12, pp. 1145 | Cited 1 time

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The formation of crystalline and amorphous solids is described using a simple glass bead demonstration and a discussion of annealing and rapid quenching on a computer. © 1999 American Association of Physics Teachers.
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01.50.My Demonstration experiments and apparatus
01.50.ht Instructional computer use
64.70.D- Solid-liquid transitions
81.30.Fb Solidification

Fluctuations in the number of particles of the ideal gas: A simple example of explicit finite-size effects

F. L. Román, A. González, J. A. White, and S. Velasco

American Journal of Physics -- December 1999 -- Volume 67, Issue 12, pp. 1149 | Cited 2 times

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The fluctuations in the number of particles of the ideal gas are calculated using the canonical and the grand canonical ensembles. The two results differ by a factor which accounts for the relative size of the total volume and the subvolume where the canonical ensemble fluctuations are calculated. This factor gives a simple example of explicit finite-size effects, because it arises from considering a fixed number of particles in the canonical ensemble. Our simulation results for the isothermal compressibility of the hard disk fluid with a finite number of particles are improved by applying this correction. © 1999 American Association of Physics Teachers.
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01.50.-i Educational aids
51.10.+y Kinetic and transport theory of gases
05.20.Gg Classical ensemble theory
05.40.-a Fluctuation phenomena, random processes, noise, and Brownian motion
51.35.+a Mechanical properties; compressibility

Dynamic light scattering

W. I. Goldburg

American Journal of Physics -- December 1999 -- Volume 67, Issue 12, pp. 1152 | Cited 11 times

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By scattering light from small particles, their geometrical structure and their state of motion can be measured. An experiment is described for measuring the diffusivity of small particles undergoing Brownian motion using the technique called photon correlation spectroscopy or dynamic light scattering. The necessary experimental apparatus and the related theory are discussed. Photon correlation spectroscopy is a powerful tool for studying the dynamical behavior of fluids near critical points, and a discussion is given of this phenomenon. The same experimental technique also can be used to study laminar or turbulent flows, and the associated theory is introduced to enable such experiments to be interpreted. © 1999 American Association of Physics Teachers.
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01.50.-i Educational aids
42.25.Fx Diffraction and scattering
78.35.+c Brillouin and Rayleigh scattering; other light scattering
05.40.Jc Brownian motion

Equilibrium time correlation functions and the dynamics of fluctuations

Marshall Luban and James H. Luscombe

American Journal of Physics -- December 1999 -- Volume 67, Issue 12, pp. 1161 | Cited 4 times

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Equilibrium time correlation functions are of great importance because they probe the equilibrium dynamical response to external perturbations. We discuss the properties of time correlation functions for several systems that are simple enough to illustrate the calculational steps involved. The discussion underscores the need for avoiding language which misleadingly suggests that thermal equilibrium is associated with a quiescent or moribund state of the system. © 1999 American Association of Physics Teachers.
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01.50.-i Educational aids
05.40.-a Fluctuation phenomena, random processes, noise, and Brownian motion
03.65.Ge Solutions of wave equations: bound states
45.30.+s General linear dynamical systems
05.70.-a Thermodynamics

Atoms in nanotubes: Small dimensions and variable dimensionality

George Stan, Silvina M. Gatica, Massimo Boninsegni, Stefano Curtarolo, and Milton W. Cole

American Journal of Physics -- December 1999 -- Volume 67, Issue 12, pp. 1170 | Cited 14 times

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Newly discovered carbon nanotubes provide an environment in which small atoms move relatively freely. An assembly of such atoms provides a realization of a quasi-one-dimensional system which can be used to illustrate the concepts of statistical physics. © 1999 American Association of Physics Teachers.
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01.50.-i Educational aids
05.20.-y Classical statistical mechanics

An introduction to breakdown phenomena in disordered systems

Rava da Silveira

American Journal of Physics -- December 1999 -- Volume 67, Issue 12, pp. 1177 | Cited 21 times

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The rupture of a medium under stress typifies breakdown phenomena. More generally, the latter encompass the dynamics of systems of many interacting elements governed by the interplay of a driving force with a pinning disorder, resulting in a macroscopic transition. A simple mean-field formalism incorporating these features is presented and applied to systems representative of fracture phenomena, social dilemmas, and magnets out of equilibrium. The similarities and differences in the corresponding mathematical structures are emphasized. The solutions are best obtained from a graphical method, from which very general conclusions may be drawn. In particular, the various classes of disorder distribution are treated without reference to a particular analytical or numerical form, and are found to lead to qualitatively different transitions. Finally, the notion of effective (or phenomenological) theory is introduced and illustrated for nonequilibrium disordered magnets. © 1999 American Association of Physics Teachers.
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01.50.-i Educational aids
05.50.+q Lattice theory and statistics (Ising, Potts, etc.)
45.30.+s General linear dynamical systems

Stars and statistical physics: A teaching experience

Roger Balian and Jean-Paul Blaizot

American Journal of Physics -- December 1999 -- Volume 67, Issue 12, pp. 1189 | Cited 6 times

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The physics of stars, their workings and their evolution, is a goldmine of problems in statistical mechanics and thermodynamics. We discuss many examples that illustrate the possibility of deepening student’s knowledge of statistical mechanics by an introductory study of stars. The matter constituting the various stellar objects provides examples of equations of state for classical or quantal and relativistic or non-relativistic gases. Maximum entropy can be used to characterize thermodynamic and gravitational equilibrium which determines the structure of stars and predicts their instability above a certain mass. Contraction accompanying radiation induces either heating or cooling, which explains the formation of stars above a minimum mass. The characteristics of the emitted light are understood from blackbody radiation and more precisely from the Boltzmann–Lorentz kinetic equation for photons. The luminosity is governed by the transport of heat by photons from the center to the surface. Heat production by thermonuclear fusion is determined by microscopic balance equations. The stability of the steady state of stars is controlled by the interplay of thermodynamics and gravitation. © 1999 American Association of Physics Teachers.
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01.50.-i Educational aids
97.10.Cv Stellar structure, interiors, evolution, nucleosynthesis, ages
97.10.Bt Star formation
05.20.-y Classical statistical mechanics
05.70.-a Thermodynamics

Interdisciplinary applications of computational statistical physics

Dietrich Stauffer

American Journal of Physics -- December 1999 -- Volume 67, Issue 12, pp. 1207 | Cited 1 time

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Biological and financial applications of computational methods in statistical physics are discussed. Examples are given of evolutionary models of sexual reproduction and stock markets. © 1999 American Association of Physics Teachers.
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01.50.-i Educational aids
02.50.Ng Distribution theory and Monte Carlo studies
87.10.-e General theory and mathematical aspects
87.23.Kg Dynamics of evolution
05.20.-y Classical statistical mechanics

Statistical thermodynamics of helix–coil transitions in biopolymers

Victor A. Bloomfield

American Journal of Physics -- December 1999 -- Volume 67, Issue 12, pp. 1212 | Cited 6 times

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Helical conformations, such as the α-helix in polypeptides and the double helix in DNA, are common structural elements in biopolymers. As the temperature is raised or the pH is changed to extremes of acidity or alkalinity, the helix becomes disordered into a random coil state. The helix–coil transition has been extensively studied, both experimentally and theoretically, as a model for conformational transitions in biopolymers and as a way to obtain information about the intermolecular forces which stabilize biopolymer structure. We develop three theoretical treatments that describe the helix–coil transition with increasing degrees of detail and rigor: the all-or-none model, the zipper model, which allows initiation of the helix only once along the polymer chain, and the matrix model, which places no restrictions on helix–coil junctions. The matrix model is mathematically similar to the familiar one-dimensional Ising model. © 1999 American Association of Physics Teachers.
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01.50.-i Educational aids
87.15.B- Structure of biomolecules

An introduction to global warming

John R. Barker and Marc H. Ross

American Journal of Physics -- December 1999 -- Volume 67, Issue 12, pp. 1216 | Cited 7 times

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The physics of climate and of climate changes associated with increasing concentrations of greenhouse gases in the atmosphere are briefly presented. Construction of a “toy model” of the climate is discussed. Possibilities for reducing carbon dioxide emissions are indicated. Degrees of uncertainty characterizing predictions of climate responses to anthropogenic greenhouse gas emissions are presented. © 1999 American Association of Physics Teachers.
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01.50.-i Educational aids
92.60.Ry Climatology, climate change and variability
92.60.Sz Air quality and air pollution

Physical aspects of the greenhouse effect and global warming

Robert S. Knox

American Journal of Physics -- December 1999 -- Volume 67, Issue 12, pp. 1227 | Cited 10 times

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According to the simplest model of the earth’s radiative balance, global warming will occur with certainty as humankind increases its production and consumption of nonsolar energy. This prediction is revisited, using a broader model that allows the greenhouse effect to be considered. The new model predicts a global warming of ΔTE=(114 K)ε, where ε is the rate of surface energy release in units of the average incident solar radiation, 342 W m−2, and ΔTE is the average temperature rise at the earth’s surface. Present values of these quantities, excluding geothermal sources, are ε=0.69×10−4 and ΔTE=7.9 mK. The model assigns a small number of optical parameters to the atmosphere and surface and qualifies the simple warming prediction: It is rigorous only if parameters other than ε are unchanged. The model is not complex and should serve as an aid to an elementary understanding of global warming. © 1999 American Association of Physics Teachers.
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01.50.-i Educational aids
89.60.-k Environmental studies
92.60.Sz Air quality and air pollution
92.60.Ry Climatology, climate change and variability

An economic analogy to thermodynamics

Wayne M. Saslow

American Journal of Physics -- December 1999 -- Volume 67, Issue 12, pp. 1239

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We develop analogies between economic systems and thermodynamics, and show how economic quantities can characterize the state of an economic system in equilibrium. We argue that just as a physical system in thermodynamic equilibrium requires a nonmechanical variable (the temperature T) to specify its state, so does an economic system. In addition, both systems must have a corresponding conjugate quantity, the entropy S. We also develop economic analogies to the free energy, Maxwell relations, and the Gibbs–Duhem relationship. Assuming that economic utility can be measured, we develop an operational definition of an economic temperature scale. We also develop an analogy to statistical mechanics, which leads to Gaussian fluctuations. © 1999 American Association of Physics Teachers.
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01.50.-i Educational aids
05.70.-a Thermodynamics
05.20.-y Classical statistical mechanics

A simple model for Brownian motion leading to the Langevin equation

Bart G. de Grooth

American Journal of Physics -- December 1999 -- Volume 67, Issue 12, pp. 1248 | Cited 9 times

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A simple one-dimensional model is presented for the motion of a Brownian particle. It is shown how the collisions between a Brownian particle and its surrounding molecules lead to the Langevin equation, the power spectrum of the stochastic force, and the equipartition of kinetic energy. © 1999 American Association of Physics Teachers.
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01.50.-i Educational aids
05.40.Jc Brownian motion

Above, below and beyond Brownian motion

Michael F. Shlesinger, Joseph Klafter, and Gert Zumofen

American Journal of Physics -- December 1999 -- Volume 67, Issue 12, pp. 1253 | Cited 15 times

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Brownian motion represents simple diffusion random walk processes. More complex random walk processes also can occur when probability distributions describing the random jump distances and times have infinite moments. We explore the manner in which these distributions can arise and how they underlie various scaling laws that play an important role in both random and deterministic systems. © 1999 American Association of Physics Teachers.
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01.50.-i Educational aids
05.40.Jc Brownian motion
02.50.-r Probability theory, stochastic processes, and statistics
05.45.Df Fractals

Teaching statistics in the physics curriculum: Unifying and clarifying role of subjective probability

Giulio D’Agostini

American Journal of Physics -- December 1999 -- Volume 67, Issue 12, pp. 1260 | Cited 5 times

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Subjective probability is based on the intuitive idea that probability quantifies the degree of belief that an event will occur. A probability theory based on this idea represents the most general framework for handling uncertainty. A brief introduction to subjective probability and Bayesian inference is given, with comments on typical misconceptions which tend to discredit it and with comparisons to other approaches. © 1999 American Association of Physics Teachers.
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01.50.-i Educational aids
02.50.Cw Probability theory

“Weather” records: Musings on cold days after a long hot Indian summer

B. Schmittmann and R. K. P. Zia

American Journal of Physics -- December 1999 -- Volume 67, Issue 12, pp. 1269 | Cited 6 times

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We present a simple introduction to the statistics of extreme values. Motivated by a string of record high temperatures in December 1998, we consider the distribution, averages, and lifetimes for a simplified model of such “records.” Our data are sequences of independent random numbers all of which are generated from the same probability distribution. A remarkable universality emerges: A number of results, including the lifetime histogram, are universal, that is, independent of the underlying distribution. © 1999 American Association of Physics Teachers.
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01.50.-i Educational aids
02.50.-r Probability theory, stochastic processes, and statistics
92.60.Wc Weather analysis and prediction

Capture of the lamb: Diffusing predators seeking a diffusing prey

S. Redner and P. L. Krapivsky

American Journal of Physics -- December 1999 -- Volume 67, Issue 12, pp. 1277 | Cited 33 times

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We study the capture of a diffusing “lamb” by diffusing “lions” in one dimension. The capture dynamics is exactly soluble by probabilistic techniques when the number of lions is very small, and is tractable by extreme statistics considerations when the number of lions is very large. However, the exact solution for the general case of three or more lions is still not known. © 1999 American Association of Physics Teachers.
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01.50.-i Educational aids
05.60.-k Transport processes
02.50.Cw Probability theory
05.20.-y Classical statistical mechanics
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An Introduction to Thermal Physics

Daniel V. Schroeder, Author and John K. Pribram, Reviewer

American Journal of Physics -- December 1999 -- Volume 67, Issue 12, pp. 1284

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Abstract Unavailable
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01.30.mp Textbooks for undergraduates
05.70.-a Thermodynamics

Thermal Physics

Ralph Baierlein, Author and Gayle Cook, Reviewer

American Journal of Physics -- December 1999 -- Volume 67, Issue 12, pp. 1285

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Abstract Unavailable
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01.30.Vv Book reviews
01.50.-i Educational aids
05.70.-a Thermodynamics
05.20.-y Classical statistical mechanics
05.30.-d Quantum statistical mechanics

A Modern Course in Statistical Physics, 2nd Edition

L. E. Reichl, Author and James H. Luscombe, Reviewer

American Journal of Physics -- December 1999 -- Volume 67, Issue 12, pp. 1285

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01.30.Vv Book reviews
05.20.-y Classical statistical mechanics

Mini-review: The Thermodynamics of Pizza: Essays on Science and Everyday Life

Harold J. Morowitz, Author and P.-M. Binder, Reviewer

American Journal of Physics -- December 1999 -- Volume 67, Issue 12, pp. 1288

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01.30.Vv Book reviews
01.75.+m Science and society
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