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Modern ergodic theory

FEB 01, 1973
There is much more to the mathematical study of Gibbs ensembles than the question of whether or not time averages and ensemble averages are equal

DOI: 10.1063/1.3127948

Joel L. Lebowitz
Oliver Penrose

The founding fathers of statistical mechanics, Boltzmann, Maxwell, Gibbs and Einstein, invented the concept of ensembles to describe equilibrium and nonequilibrium macroscopic systems. In trying to justify the use of ensembles, and to determine whether the ensembles evolved as expected from nonequilibrium to equilibrium, they introduced further concepts such as “ergodicity” and “coarse graining.” The use of these concepts raised mathematical problems that they could not solve, but like the good physicists they were they assumed that everything was or could be made all right mathematically and went on with the physics.

References

  1. 1. V. I. Arnold, A. Avez, Ergodic Problems of Statistical Mechanics, Benjamin, New York (1968);
    J. Ford, “The Transition from Analytic Dynamics to Statistical Mechanics,” to be published in Advances in Chemical Physics;
    J. L. Lebowitz, “Hamiltonian Flows and Rigorous Results in Non‐equilibrium Statistical Mechanics,” in Proceedings of the IUPAP Conference on Statistical Mechanics, University of Chicago Press (1972);
    O. Lanford, “Ergodic Theory and Approach to Equilibrium for Finite and Infinite Systems,” to be published in Proceedings of the 100th Anniversary of the Boltzmann Equation, Vienna, 1972;
    Ya. G. Sinai, “Ergodic Theory,” to be published in Proceedings of the 100th Anniversary of the Boltzmann Equation;
    A. S. Wightman, in Statistical Mechanics at the Turn of the Decade (E. G. D. Cohen, ed.) Marcel Dekker, New York (1971).

  2. 2. Ya. G. Sinai, Sov. Math.‐Dokl. 4, 1818 (1963);
    “Ergodicity of Boltzmann’s Equations” in Statistical Mechanics, Foundations and Applications (T. A. Bak, ed.) Benjamin, New York (1967);
    Russian Mathematical Reviews 25, 137 (1970).

  3. 3. G. H. Walker, J. Ford, Phys. Rev. 188, 416 (1969).https://doi.org/PHRVAO

  4. 4. O. Penrose, Foundations of Statistical Mechanics, Pergamon, Oxford (1970) chapter III.

  5. 5. D. ter Haar, Elements of Statistical Mechanics, Holt, Rinehart and Winston, New York (1964), Appendix 1, paragraph 5;
    O. Penrose, Foundations of Statistical Mechanics, Pergamon, Oxford (1970), page 40;
    S. G. Brush, Transport Theory and Statistical Physics 1(4), 287 (1971).https://doi.org/TTSPB4

  6. 6. V. I. Arnold, A. Avez, ref. 1, page 16.

  7. 7. A. N. Kolmogorov, “Address to the 1954 International Congress of Mathematicians,” [translated in R. Abrahams, Foundations of Mechanics, Benjamin, New York (1967), Appendix D].

  8. 8. Enrico Fermi: Collected Papers, Volume II, University of Chicago Press, Chicago (1965) page 978.

  9. 9. G. H. Lunsford, J. Ford, J. Math. Phys. 13, 700 (1972).https://doi.org/JMAPAQ

  10. 10. M. Hénon, C. Heiles, Astron. J. 69, 73 (1964).https://doi.org/ANJOAA

  11. 11. V. I. Arnold, A. Avez, ref. 1, page 25.

  12. 12. J. von Neumann, Annals of Math. 33, 587 (1932).

  13. 13. E. Hopf, J. Math. and Phys. 13, 51 (1934);
    Ergoden Theone, Springer, Berlin (1937).

  14. 14. J. W. Gibbs, Elementary Principles in Statistical Mechanics, Dover, New York (1960) page 144.

  15. 15. H. Poincaré, Acta Math. 13, 1 (1890); https://doi.org/ACMAA8
    Oeuvres 7, 262;
    J. W. Gibbs, reference 14, page 139.

  16. 16. T. Erber, B. Schweizer, A. Sklar, to be published in Comm. Math. Phys.

  17. 17. D. Ornstein, B. Weiss, to be published in Israel J. Mathematics.

  18. 18. P. R. Halmos, Lectures on Ergodic Theory, Mathematical Soc. of Japan (1965) page 9;
    V. I. Arnold, A. Avez, reference 1, page 8.

More about the Authors

Joel L. Lebowitz. Yeshiva University, New York.

Oliver Penrose. Mathematics Faculty, Open University, Walton, UK.

This Content Appeared In
pt-cover_1973_02.jpeg

Volume 26, Number 2

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