Abstract
In this chapter I explore Planck’s radiation theory from his preliminary studies (1896) through his more mature Pentalogy (1897–1899). Planck viewed the problem of the black-body radiation very differently from Wien and the majority of his contemporaries. In particular, Planck was not primarily interested in deriving a radiation law. Instead, he considered heat radiation as an ideal case to support his strict view of thermal irreversibility. He wanted to prove that electromagnetic radiation in a cavity, when suitably stimulated, reaches irreversibly a form of stable thermal equilibrium. Initially, Planck thought that this statement could be demonstrated as a consequence of the electromagnetic features of the problem. Boltzmann jumped in and showed that this could not possibly be the case. In the second part of the Pentalogy, Planck changed strategy. He modified the morphology of his theory to accommodate new resources and gave a more central role to some symbolic practices, notably Fourier series. The central move of the reorganization of his theory was the introduction of the hypothesis of natural radiation as a way to draw a divide between the macroscopic and microscopic state. Planck obtained his argument for irreversibility, but he had to pay a prize for it: his entire program depended essentially on the validity of Wien’s law.
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Notes
- 1.
Important theoretical research on the propagation of spherical waves had been already carried out independently by Rowland (1884). For this reason, it is not uncommon to find in the literature the term ‘Rowland-Hertz oscillator’.
- 2.
On this point see (Buchwald 1998).
- 3.
- 4.
Planck assumes that no Joule effect takes place, and hence the energy emitted is due to the oscillation and not to transformation into other kinds of energy.
- 5.
In particular, he shows that if the resonator is small with regard to the wavelength of the interacting radiation, it is possible to simplify the expression for the dipole moment and its derivative (Darrigol 1992). Ultimately, Planck’s theory of resonator relies on a clear-cut distinction between two lengths of different orders of magnitude: the characteristic wavelength involved in the resonator-field interaction and the geometric lengths ascribed to the material system (size of the cavity, linear dimension of the resonator). The latter must be much larger than the former to apply the usual laws of refraction and reflection without the intervention of diffraction phenomena.
- 6.
Planck arrives at the second order from the usual third order equation by considering only real solutions.
- 7.
Here one can see at work an example of the difference between ‘physics of problems’ and ‘physics of principle’ recently outlined by Seth (2010).
- 8.
These kinds of assumptions, similarly to the approximations on the linear size of the resonator, are common in Planck’s theory and, more generally, in theories concerned with drawing macroscopic consequences from a microscopic model.
- 9.
Note that this consequence also follows from Wien’s thermodynamic argument that only higher frequencies can produce thermal effects (Wien 1893). Though, Planck does not quote Wien: he wants to make a general argument on the behavior of an oscillating structure separate from the nature of heat radiation.
- 10.
The complete definition of the SZA is more complex; see (Ehrenfest and Ehrenfest 1911, pp. 4–13).
- 11.
Boltzmann (1877, 1909, Vol. II, pp. 164–223). According to common wisdom, Boltzmann did not realize the probabilistic implications of his theory until Loschmidt’s reversibility objection (Klein 1973; Kuhn 1978; Brown et al. 2009). However, this claim does not stand before a careful examination of Boltzmann’s papers during the period of 1868–1877. I have argued elsewhere that Boltzmann was aware since the late 1860 s that irreversibility was a matter of probability (Badino 2011).
- 12.
Indeed, Planck was right: Maxwell’s distribution is the only one that fulfills the SZA applied to reversed collisions (Ehrenfest and Ehrenfest 1911, pp. 11–13). In that case, however, the SZA ceases to be a probabilistic assumption.
- 13.
Boltzmann to Eilhard Wiedemann, 20 March 1896, (Höflechner 1994, Doc. 427).
- 14.
That such a time exists, follows from the condition above that only the harmonics with very high frequency and short period play a role in heat radiation.
- 15.
The amplitude \(C_n\) is related to the amplitude of the Hertz vector, while \(\theta _n\) are its phase constants. The index \(a = 1, 2, 3, \dots \) comes from an ingenious rearrangement of the harmonics that Planck operates to simplify the calculation of the Poynting vector. The cross products can be ordered in groups of harmonics separated by an increasing distance a.
- 16.
The integers \(k_n\) are related to the natural period of the resonator. Essentially, they select the acceptable solutions in terms of the resonance interaction. The amplitude \(D_n\) is related to the field amplitude \(C_n\) via special phase parameters.
- 17.
A clarification of this argument would come in the fourth paper. There, Planck shows that the Fourier series of the radiation intensity is time-dependent in two different ways: in the main series, the time appears in periodic terms, while in the Fourier coefficients, time is the argument of functions that are in general aperiodic. The equilibration process acts precisely on these aperiodic terms (Planck 1898b, 1958, Vol. I, p. 541).
- 18.
In fact, the energetic difference between the primary and the secondary field is precisely the contribution of the resonator.
- 19.
The parameter \(\gamma \) confines the series to terms very close to the characteristic frequency of the resonator.
- 20.
If the damping process lasts too long, the resonator will still be in vibration when a new train of waves impinges on it, and the energy given off will be the superposition of the radiations that arrived at different times instead of the component of a single wave.
- 21.
The parameter \(\delta \) plays the same role as the parameter \(\gamma :\) it constraints the series in order that only frequencies very close to the characteristic frequency carry a non-negligible energy.
- 22.
- 23.
- 24.
- 25.
Thomas Kuhn has suggested that the molar/molecular distinction allowed Boltzmann to combine statistical and dynamical phraseology because it corresponds to the micro/macro distinction (Kuhn 1978, pp. 54–60). This terminology, however, was not new. J.J. Thomson, for instance, used a similar distinction to stress the uncontrollability of the molecular behavior (Thomson 1887). The molar/molecular distinction meant therefore something slightly different from the micro/macro divide, because the emphasis was preferably on the possibility of acting on microscopic states. It is precisely this point that Boltzmann wants to make with the concept of molecular chaos.
- 26.
Ultimately, Boltzmann’s point amounts to distinguishing between equilibrium as a state described by Maxwell’s distribution and as the end point of a mechanical trajectory. In other words, it concerns the epistemic surplus of two sets of symbolic practices: probabilistic tools and mechanical methods.
- 27.
In effect, Kuhn regards the introduction of the HNR as the entering of statistics into radiation theory. Darrigol is more cautious and points out that Planck did not need to install Boltzmann’s full package in his theory (Darrigol 1992, pp. 51–54).
- 28.
On this point see also (Seth 2010, pp. 119–126).
- 29.
- 30.
- 31.
Letter from Planck to Runge, 14 October 1898; see also (Planck 1958, Vol. I, p. 623).
- 32.
One formal difficulty that Planck does not succeed in overcoming is the dependence of the spectral component on the damping constant of the analyzing resonator. At the end, he is forced to drop it on the grounds that an acceptable spectral component cannot possibly depend on the features of the ideal apparatus used to measure it.
- 33.
It is interesting to note that Planck does not write explicitly the relation between energy density and average energy of the resonator:
which is usually associated with his electromagnetic radiation theory. To be sure, this relation can be easily derived from Planck’s equations, but it is worth stressing that, at this stage, energy density and resonator energy are not the two macroscopic quantities he wants to relate. It is much more important for his irreversibility argument to work with the polarized intensity.
- 34.
For a discussion of this aspect see (Badino and Robotti 2001).
- 35.
References
Badino M (2009) The odd couple: Boltzmann, Planck and the application of statistics to physics (1900–1913). Annalen der Physik 18(2–3):81–101
Badino M (2011) Mechanistic slumber vs. statistical insomnia: the early phase of Boltzmann’s H-theorem (1868–1877). Eur Phys J H 36:353–378
Badino M, Robotti N (2001) Max Planck and the constants of nature. Ann Sci 58:137–162
Bjerknes V (1891a) Über den zeitlichen Verlauf der Schwingungen im primären Hertz’schen Leiter. Annalen der Physik 44:513–526
Bjerknes V (1891b) Über die Erscheinung der multiplen Resonanz electriscer Wellen. Annalen der Physik 44:92–101
Boltzmann L (1872) Weitere Studien über das Wärmegleichgewicht unter Gasmolekülen. Sitzungsberichte der Akademie der Wissenschaften zu Wien 66:275–370
Boltzmann L (1877) Über die Beziehung zwischen dem zweiten Hauptsatze der mechanischen Wärmetheorie und der Wahrscheinlichkeitsrechnung respective den Sätzen über das Wärmegleichgewicht. Sitzungsberichte der Akademie der Wissenschaften zu Wien 76:373–435
Boltzmann L (1894) Über den Beweis des Maxwellschen Geschwindigkeitsverteilungsgesetzes unter Gasmolekülen. Annalen der Physik 53:955–958
Boltzmann L (1895a) Erwiderung an Culverwell. Nature 51:581
Boltzmann L (1895b) Nochmals das Maxwellsche Verteilungsgesetz der Geschwindigkeiten. Annalen der Physik 55:223–224
Boltzmann L (1895c) On certain questions of the theory of gases. Nature 51:413–415
Boltzmann L (1895d) On the minimum theorem in the theory of gases. Nature 52:211
Boltzmann L (1896) Entgegnung auf die wärmetheoretischen Betrachtungen des Hrn. E. Zermelo. Annalen der Physik 57:773–784
Boltzmann L (1897a) Über irreversible Strahlungsvorgänge I. Sitzungsberichte der Preussischen Akademie der Wissenschaften 2:660–662
Boltzmann L (1897b) Über irreversible Strahlungsvorgänge II. Sitzungsberichte der Preussischen Akademie der Wissenschaften 2:1013–1018
Boltzmann L (1898a) Über die sogenannte H-Kurve. Mathematische Annalen 50:325–332
Boltzmann L (1898b) Über vermeintlich irreversible Strahlungsvorgänge. Sitzungsberichte der Preussischen Akademie der Wissenschaften 1:182–187
Boltzmann L (1898c) Vorlesungen über Gastheorie. Barth, Leipzig
Boltzmann L (1909) Wissenschaftliche Abhandlungen. Barth, Leipzig
Bremmer H (1958) Propagation of electromagnetic waves. In: Flügge S (ed) Electric Fields and Waves, Handbuch der Physik, vol 15. Springer, Berlin, pp 423–639
Brown HR, Myrvold W, Uffink J (2009) Boltzmann’s H-theorem, its discontents, and the birth of statistical mechanics. Stud Hist Philos Mod Phys 40:174–191
Bryan GH (1894a) The kinetic theory of gases I. Nature 51:176
Bryan GH (1894b) The kinetic theory of gases II. Nature 51(1311):152
Bryan GH (1894c) The kinetic theory of gases III. Nature 51(1312):176
Bryan GH (1895) The assumption in Boltzmann’s minimum theorem. Nature 52:29–30
Buchwald J (1998) Reflections on Hertz and the Hertzian dipole. In: Baird D, Hughes RIG, Nordmann A (eds) Heinrich Hertz: classical physicists. Modern Philosopher, Kluwer Academic, London, pp 269–280
Burbury SH (1894) Boltzmann’s minimum function. Nature 51(1308):78–79
Burbury SH (1902) On irreversible processes and Planck’s theory in relation thereto. Philos Mag 3(14):225–240
Culverwell EP (1890) Note on Boltzmann’s Kinetic theory of gases, and on Sir W. Thomson’s Address to Section A, British Association, 1884. Philos Mag 30(182):95–99
Culverwell EP (1894) Dr. Watson’s proof of Boltzmann’s theorem on permanence of distributions. Nature 50(1304):617
Culverwell EP (1895a) Boltzmann’s minimum theorem. Nature 51(1315):246
Culverwell EP (1895b) Professor Boltzmann’s letter on the kinetic theory of gases. Nature 51(1329):581
Darrigol O (1992) From c-numbers to q-numbers. The classical analogy in the history of quantum theory. University of California Press, Berkeley
Dias PMC (1994) “Will someone say exactly what the H-theorem proves?” A study of Burbury’s condition A and Maxwell’s proposition II. Arch Hist Exact Sci 46(4):341–366
Ehrenfest P (1905) Über die physikalischen Voraussetzungen der Planck’schen Theorie der irreversiblen Strahlungsvorgänge. Sitzungsberichte der Akademie der Wissenschaften zu Wien 114:1301–1314
Ehrenfest P, Ehrenfest T (1911) The conceptual foundations of the statistical approach in mechanics. Dover, New York
Essex EA (1977) Hertz vector potentials of electromagnetic theory. Am J Phys 45(11):1099–1101
Gouy LG (1886) Sur le mouvement lumineux. Journal de Physique Théorique et Appliquée 5:354–362
Hertz H (1889) Die Kräfte electrischer Schwingungen, behandelt nach der Maxwell’schen Theorie. Annalen der Physik 36(1):1–22
Höflechner W (1994) Ludwig Boltzmann. Akademische Druck und Verlaganstalt. Leben und Briefe, Graz
Jeans JH (1903) The kinetic theory of gases developed from a new standpoint. Philos Mag 5(30):597–620
Klein MJ (1973) The development of Boltzmann’s statistical ideas. Acta Phys Austriaca Suppl 10:53–106
Kuhn T (1978) Black-body theory and the quantum discontinuity, 1894–1912. Oxford University Press, Oxford
Loschmidt J (1876) Über den Zustand des Wärmegleichgewichtes eines Systems von Körpern mit Rücksicht auf die Schwerkraft. Sitzungsberichte der Akademie der Wissenschaften zu Wien 73:128–142
Maxwell J (1867) On the dynamical theory of gases. Philos Trans Roy Soc Lond 157:49–88
Maxwell J (1871) Theory of heat. Longmans, Green and Co., London
Needell A (1980) Irreversibility and the failure of classical dynamics: Max Planck’s work on the quantum theory, 1900–1915. PhD thesis, University of Michigan, Ann Arbor
Planck M (1879) Über den zweiten Hauptsatz der mechanischen Wärmetheorie. Ackermann, München
Planck M (1891) Allgemeines zur neueren Entwicklung der Wärmetheorie. Zeitschrift für physikalische Chemie 8:647–656
Planck M (1894) Antrittsrede, gehalten am 28. Juni 1894 zur Aufnahme in die Akademie. Sitzungsberichte der Preussischen Akademie der Wissenschaften 2:641–644
Planck M (1895) Über den Beweis des Maxwellschen Geschwindigkeitsverteilungsgesetzes unter den Gasmolekülen. Annalen der Physik 55:220–222
Planck M (1896) Absorption und Emission electrischer Wellen durch Resonanz. Annalen der Physik 57(1):1–14
Planck M (1897a) Über electrische Schwingungen, welche durch Resonanz erregt und durch Strahlung gedämpft werden. Annalen der Physik 60:577–599
Planck M (1897b) Über irreversible Strahlungsvorgänge. 1. Mitteilung. Sitzungsberichte der Preussischen Akademie der Wissenschaften 1:57–68
Planck M (1897c) Über irreversible Strahlungsvorgänge. 2. Mitteilung. Sitzungsberichte der Preussischen Akademie der Wissenschaften 2:715–717
Planck M (1898a) Über irreversible Strahlungsvorgänge. 3. Mitteilung. Sitzungsberichte der Preussischen Akademie der Wissenschaften 1:1122–1145
Planck M (1898b) Über irreversible Strahlungsvorgänge. 4. Mitteilung. Sitzungsberichte der Preussischen Akademie der Wissenschaften 2:449–476
Planck M (1899) Über irreversible Strahlungsvorgänge. 5. Mitteilung. Sitzungsberichte der Preussischen Akademie der Wissenschaften 1:440–480
Planck M (1900) Über irreversible Strahlungsvorgänge. Annalen der Physik 1:69–122
Planck M (1902) Über die Natur des weissen Lichtes. Annalen der Physik 7:390–400
Planck M (1906) Vorlesungen über die Theorie der Wärmestrahlung. Barth, Leipzig
Planck M (1958) Physikalische Abhandlungen und Vorträge. Vieweg, Sohn, Braunschweig
Rayleigh JWS (1889) On the character of the complete radiation at a given temperature. Philos Mag 27:460–469
Rowland HA (1884) On the propagation of an arbitrary electro-magnetic disturbance, on spherical waves of light and the dynamical theory of diffraction. Am J Math 6(4):359–381
Schuster A (1894) On interference phenomena. Philos Mag 37:509–545
Seth S (2010) Crafting the quantum. Arnold sommerfeld and the practice of theory, 1890–1926. MIT Press, Cambridge
Thomson JJ (1887) Some applications of dynamical principles to physical phenomena. Part II. Philos Trans Roy Soc Lond 178:471–526
Watson HW (1893) A treatise on the Kinetic theory of gases, 2nd edn. Clarendon Press, Oxford
Watson HW (1894) Boltzmann’s minimum theorem. Nature 51(1309):105
Wien W (1893) Die obere Grenze der Wellenlängen, welche in der Wärmestrahlung fester Körper vorkommen können; Folgerungen aus dem zweitem Hauptsatz der Wärmetheorie. Annalen der Physik 49:633–641
Wien W (1909) Theorie der strahlung. In: Sommerfeld A (ed) Encyklopädie der mathematischen Wissenschaften, vol 3. Teubner, Leipzig, pp 282–357
Zermelo E (1896) Über einen Satz der Dynamik und die mechanische Wärmetheorie. Annalen der Physik 57:485–494
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Badino, M. (2015). Planck’s Theory of Radiation. In: The Bumpy Road. SpringerBriefs in History of Science and Technology. Springer, Cham. https://doi.org/10.1007/978-3-319-20031-6_3
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