jerzy karpiuk photochemistry and spectroscopy laboratory, ipc pas [email protected]
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Forgotten experiments and the Planck’s radiation formula. On the experimenal context at the birth of quantum physics. Jerzy Karpiuk Photochemistry and Spectroscopy Laboratory, IPC PAS [email protected]. 14.12.1900 – birth date * of quantum theory. - PowerPoint PPT PresentationTRANSCRIPT
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Forgotten experiments and Forgotten experiments and the the Planck’s radiation formula.Planck’s radiation formula. On the experimenal context at On the experimenal context at the birth of quantum physics.the birth of quantum physics.
Jerzy KarpiukJerzy KarpiukPhotochemistry and Spectroscopy Laboratory, IPC PASPhotochemistry and Spectroscopy Laboratory, IPC PAS
[email protected]@ichf.edu.pl
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* A. Sommerfeld, Atombau und Spektrallinien, 1919, p. 4
14.12.1900 – birth date14.12.1900 – birth date** of quantum of quantum theorytheory
"Das war eine rein formale Annahme, und ich dachte mir eigentlich nicht viel dabei, sondern eben nur das, dass ich unter allen Umständen, koste es, was es wolle, ein positives Resultat herbeiführen musste.” (1931)
„It was a purely formal assumption and I really did not give it much thought except that no matter what the cost, I must bring about a positive end.” (1931)
Max Karl Ernst Max Karl Ernst Ludwig Ludwig Planck (1858 –1947)Planck (1858 –1947)
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Traditional point of viewTraditional point of view
„It is rare in any form of progress or in any discovery that the success can be with truth attributed to one man... But of Planck it can be said, and it is universally true that the formation of the quantum theory is his alone.”
H. T. Flint, Nature 181 (1958) 1098
„Planck’s unique position is best illustrated by what is in my opinion the singular fact that he had no precursors or competitors whose thoughts moved in a similar direction.”
E. Segrè, Phys. Bl. 23 (1967) 62
„It is rare in any form of progress or in any discovery that the success can be with truth attributed to one man... But of Planck it can be said, and it is universally true that the formation of the quantum theory is his alone.”
H. T. Flint, Nature 181 (1958) 1098
„Did Planck create them out of nothing?”
H. Kangro, Early History of Planck’s Radiation Law (1976) p. 1
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Planck’s opinion ...Planck’s opinion ...M. Planck on the nomination for the Nobel Prize in physics for 1908:
„It was not so that theoretical work paved the way for the experimental studies; more correctly is to say it was just the opposite."
The Prize was then to be shared by „a leading theoretician and a leading experimentalist, in this case perhaps Lummer".R. Torge: Otto Lummer, Fritz Reiche, Mieczysław Wolfke: Szkice biograficzne. Postępy Fizyki 53 (2002) 201
„It seems as if the formula, once put in mathematical form, survived quite well, whereas the experiments on which it was first founded have relatively rapidly fallen into oblivion.”
H. Kangro, Early History of Planck’s Radiation Law, 1976, p. 2
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„„Rosencrantz i Guildenstern are Rosencrantz i Guildenstern are dead”dead”
Allan Franklin, Allan Franklin, The Neglect of ExperimentThe Neglect of Experiment, , 19861986
One of the great anticlimaxes in all of literature occurs at the end of Shakespeare’s Hamlet. On stage strewn with noble and heroic corpus —Hamlet, Laertes, Claudius, and Gertrude — the ambassadors from England arrive and announce that “Rosencrantz and Guildenstern are dead”. No one cares. A similar reaction might be produced among a group of physicists, or even among historians and philosophers of science, were someone to announce that “Lummer and Pringsheim are dead”.
Jeden z największych zawodów w całej literaturze występuje pod koniec „Hamleta” Szekspira. Na scenę usłaną ciałami bohaterów – Hamleta, Laertesa, Klaudiusza i Gertrudy wkraczają ambasadorowie z Anglii I zawiadamiają, że “Rosenkranz i Guildestern nie żyją”. Nikt się tym nie przejmuje. Podobna reakcja mogłaby wystąpić wśród fizyków lub nawet historyków i filozofów nauki, gdyby ktoś zawiadomił, że “Lummer i Pringsheim nie żyją”.
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),( Tu
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Kirchhoff’s problem – Kirchhoff’s problem – 18601860
),(
),(),(
Ta
TeTu
G. Kirchhoff: Über das Verhältnis zwischen dem Emissionsvermögen und dem Absorptions-vermögen der Körper für Licht und Wärme, Annalen der Physik 19 (1860) 275.
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Kirchhoff’s black body definition:Kirchhoff’s black body definition: a(a(νν,T),T) = 1 = 1Experimental problems:- radiation source- detector- method of spectral
measurements
),(
),(),(
Ta
TeTu
G. Kirchhoff, Annalen der Physik 19 (1860) 275.
When a space is surrounded by bodies of the same temperature, and no rays can penetrate through these bodies, every ray in the interior of the space is so constituted, with respect to its quality and intensity, as if it proceeded from a perfectly black body of the same temperature, and is therefore independent of the nature and form of the bodies, and only determined by the temperature.”
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Frederick William Herschel (1738-1822 )
1800 – discovery of infrared radiation
Radiant heat: in the search Radiant heat: in the search for for u(u(νν,T),T)
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F. W. Herschel, 1800: prism (glass) + thermometer
J. H. Müller, 1859: rock salt prism + thermopile
AndrAndréé P. P. Crova (1833- P. P. Crova (1833- 1907)1907)
Light sources in order of increasing temperature: stearin candle, coal gas flame, electric arc light, sun
Shift of the maximum with temperature
John Tyndall (1820- John Tyndall (1820- 1893)1893)
J. Tyndall, 1864: rock salt prism + thermopile
electric carbon arc light spectrum
Refraction spectra
red blue
visible radiation
invisibleradiation
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Thermo-electric pile Thermo-electric pile (1860-s)(1860-s)
bismuthantimony
J. Tyndall, J. Tyndall, Heat considered as a mode of motionHeat considered as a mode of motion, , 18641864, , Six lectures on Six lectures on light light , , 1872-31872-3
"My assistant stands several feet off. I turn the thermopile towards him. The heat from his face, even at this distance, produces a deflection of 90 degrees [on the galvanometer dial]. I turn the instrument towards a distant wall, judged to be a little below the average temperature of the room. The needle descends and passes to the other side of zero, declaring by this negative deflection that the pile feels the chill of the wall."
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J. Stefan (1879) + L. Boltzmann (1884) = Stefan-Boltzmann law
4
0
),()( TdTuTU
Deduced by J. Stefan from J. Tyndall’s experiments
L. Boltzmann derived theoretically the law studying a heat engine with light as a working matter
„From weak red heat (about 525 C) to complete white heat (about 1200 C) the intensity of radiation increases from 10.4 to 122, thus nearly 12-fold (more precisely 11.7). The ratio of the absolute temperature 273 + 1200 and 273 + 525 raised to the fourth power gives 11.6.”
Stefan-Boltzmann lawStefan-Boltzmann law
J. Stefan, Über die Beziehung zwischen der Wärmestrahlung und der Temperatur, Mathemat. –Naturwiss. Classe Abteilung 2 79 (1879), pp. 391–428.
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Samuel P. Langley’s bolometer - Samuel P. Langley’s bolometer - 18781878
„Langley's bolometer was so sensitive that it could detect thermal radiation from a cow a quarter of a mile away.”
BolometerBolometer improved resistance improved resistance thermometerthermometer
1880: 1880: T T 10 10-5-5 °C, ± 1% °C, ± 1%
Two platinum strips, covered with lampblack, one strip was shielded from the radiation and one exposed to it. The strips formed two branches of a Wheatstone bridge which was fitted with a sensitive galvanometer and connected to a battery.
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Bolometer in the service of Bolometer in the service of photometryphotometry
„...we are facing a big problem, awaiting for solution. I mean the relationship between the temperature and radiation, as we do know virtually nothing about the issue, but once we know it, we will have a new view on almost all the processes occurring in nature.”
S. P. Langley, 1889 (S. Barr, Am. J. Phys. 28 (1960) 42)
0°C – 10 m100 °C – 7.5 m
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2/31 exp)(
T
cTBI
Michelson equation (1887) described well Langley’s results.
W. Michelson, J. de Phys. 6 (1887) 467.
In the derivation Michelson used Maxwell’s velocity distribution law.
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Competition between electrical and gas Competition between electrical and gas lightinglighting
Platinum plate 1 cmPlatinum plate 1 cm22 with T with Tmm Pt (2042 K) ( Pt (2042 K) (18841884))
Hefner candle, standard in Germany (1883 – Hefner candle, standard in Germany (1883 – 1947)1947)(amyl acetate, PTR) (amyl acetate, PTR) sensitive to fluctuations in air humiditysensitive to fluctuations in air humidity
A search for reliable luminosity A search for reliable luminosity standardstandard
Carcel lamp, standard in FranceCarcel lamp, standard in France(rapeseed oil - 42 g/h)(rapeseed oil - 42 g/h)
Light sources of that time (incandescent lamp [1879] of gas lamp radiated a lot of energy in the invisible part of the spectrum – radiometry must have been developed.
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The place of birth of quantum physics: The place of birth of quantum physics: Physikalisch-Technische ReichsanstaltPhysikalisch-Technische Reichsanstalt
PTR Observatory (clock hall) and not the lecture PTR Observatory (clock hall) and not the lecture room of the Physical Institute at Berlin’s room of the Physical Institute at Berlin’s
UniversityUniversity
18871887H. von HelmholtzH. von Helmholtz
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1898 Act on 1898 Act on electrical unitselectrical units
PTR, 1898PTR, 1898
The Ohm is a unit of electrical resistance. It is equal to the resistance of a mercury column at a temperature of melting ice, with a length, at consistently identical cross section of 1 mm2, of 106.3 cm, and a mass of 14,4521 gram.
We Wilhelm, by the grace of God German Emperor, King of Prussia, etc. do order in the name of the German Empire…
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Radiation Laboratory at Radiation Laboratory at PTRPTR
surface bolometersurface bolometer
Lummer-Broduhn Lummer-Broduhn spectral bolometerspectral bolometer
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Development of detection Development of detection techniquestechniques
Lummer’s bolometrLummer’s bolometr: : T T 10 10-7-7 °C, ± 1% °C, ± 1%
The purpose of optical studies is to confirm the The purpose of optical studies is to confirm the fundamental laws of heat and light radiation.fundamental laws of heat and light radiation.
PTR Report PTR Report 1899/1900:1899/1900:
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Microstructural detectors (1890-s)Microstructural detectors (1890-s)
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Ferdinand Ferdinand Kurlbaum Kurlbaum
1857 - 19271857 - 1927
Heinrich RubensHeinrich Rubens1865 - 19221865 - 1922
Otto LummerOtto Lummer1860 - 19251860 - 1925
Ernst PringsheimErnst Pringsheim1859 - 19171859 - 1917
Wilhelm WienWilhelm Wien1864 - 19281864 - 1928
Friedrich PaschenFriedrich Paschen1865 - 19471865 - 1947
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J. Stefan (1879) + L. Boltzmann (1884) = Stefan-Boltzmann law
4
0
),()( TdTuTU
W. Wien (1893) - Wien displacement law
)/(),( 3 TfTu
W. Wien (1896) - Wien law (until mid 1900 in agreement with experimental data)
TcTu
exp8
),( 3
3
Stefan-Boltzmann law Stefan-Boltzmann law confirmed up to ± 1%confirmed up to ± 1%
(surface bolometer)(surface bolometer)
Wien displacement Wien displacement law confirmedlaw confirmed
(linear bolometer)(linear bolometer)
Radiation lawsRadiation laws
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TcTu
exp8
),( 3
3Wien law - 1896Wien law - 1896
W. Wien, Annalen der Physik 58 (1896) 662.
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Initially the importance of „blackness” of the bodies for emitted radiation was neglected.(„man hat überhaupt außer acht gelassen”)
As black bodies blackened metal plates were used that can be used as black bodies only in a limited T range (Ch. Christiansen, 1880)
Wien i Lummer (1895): „we have to abandon these artificially blackened plates”:
(“man muß überhaupt von den künstlich geschwärzten Blechen absehen” und stattdessen “die Strahlung eines schwarzen Körpers als den Zustand des Wärmegleichgewichts aufzufassen... Um hierauf auch eine praktisch brauchbare Methode zu gründen, durch die man die Strahlung eines schwarzen Körpers in beliebiger Annäherung herstellen kann, muss man einen Hohlraum auf gleichmässige Temperatur bringen und durch die Öffnung seine Strahlung nach aussen gelangen lassen”.)
W. Wien, O. Lummer, Annalen der Physik 56 (1895) 453.
Should black body be Should black body be black?black?
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O. Lummer & E. Pringsheim: 1895 - O. Lummer & E. Pringsheim: 1895 - 1898 1898
liquid airliquid air boiling boiling waterwater
boiling niterboiling niter
-188-188°°CC
100100°°CC
680680°°CC
12001200°°CC
hot gashot gas
Cavities:- cylindrical and spherical, metal- double-wall, spherical, porcelain- surface blackened with lampblack,
FeO or UO2
D. Hoffmann, On the Experimental Context of Planck’s Foundation of Quantum Theory, 2000
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Black body:Black body:platinum plate 0,01 mmplatinum plate 0,01 mm100 A / 1500°C100 A / 1500°Cgraphite - 2100°C (1903)graphite - 2100°C (1903)
Electrically annealed black bodyElectrically annealed black body(Lummer & Kurlbaum, 1898)(Lummer & Kurlbaum, 1898)
W. Wien, O. Lummer, Annalen der Physik 56 (1895) 453.
40 40 cmcm
4 cm4 cm
Lummer:Lummer: Betriebsblindheit professional blindness professional blindness
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H. J. Kostkowski, R. D. Lee, Theory and methods of optical pyrometry, NBS Special Publication 300: Precision measurements and calibration. Temperature, Washington 1968, p. 361
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Precision measurements of black body Precision measurements of black body spectrumspectrum
Tests of Wien Tests of Wien energy energy distribution law distribution law (since 1899 - (since 1899 - Wien-Planck Wien-Planck e.d.l.e.d.l.))
SpectrobolometSpectrobolometerer
Ta
bc
Tu exp
8),( 3
3
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Deviations from Deviations from Wien distributionWien distribution
Feb. 1899:Feb. 1899:measurements up to measurements up to 6 6 m, T: 800 - 1400°C m, T: 800 - 1400°C „indicate small „indicate small deviations from deviations from WienWien--Planck Planck distributiondistribution””
O. Lummer, E. Pringsheim, Verh. Deutsch. Phys. Gesell. 1 (1899) 36.
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Nov. 1899:Nov. 1899: measurements up measurements up to 8,3 to 8,3 m, T up to 1650°C: m, T up to 1650°C: „the discrepances between „the discrepances between the theory and experiment the theory and experiment are of systematic nature”are of systematic nature”
O. Lummer, E. Pringsheim, Verh. Deutsch. Phys. Gesell. 1 (1899) 226.
Deviations from Deviations from Wien distributionWien distribution
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Feb. 1900:Feb. 1900: in mesurements in mesurements up to 18 up to 18 m, T up to m, T up to 1772°C: „the differences 1772°C: „the differences between the theory and between the theory and experiment reached 50%”experiment reached 50%”
O. Lummer, E. Pringsheim, Verh. Deutsch. Phys. Gesell. 2 (1900) 163.
Wien law is not generally valid, but … Wien law is not generally valid, but … justifiedjustified
Feb. 1900:Feb. 1900: being aware of being aware of the above, Planck the above, Planck publishes justification of publishes justification of Wien law using a non-Wien law using a non-mechanistic, purely mechanistic, purely thermodynamic approach thermodynamic approach to the radiation fieldto the radiation field
M. Planck „Entropie und Temperatur strahlender Wärme”, Annalen der Physik 1 (1900) 719.
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Entropy and energy of a system of n Entropy and energy of a system of n „resonators”„resonators”
M. Planck „Entropie und Temperatur strahlender Wärme”, Annalen der Physik 1 (1900) 719.
Ua
US
2
2
)/ln(1
UUS
TUS 1
)ln( UUS )exp(T
U
TcTu
exp8
),( 3
3
)(, f
nUU
UUfndUUfUdUdS
n
nnnn
)()(
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EquationEquationss
Planck(Oct. 19, 1900)
Wien(PTR, 1896)
Lummer &Pringsheim(PTR, Feb. 1900)
Thiesen(PTR, Feb. 1900)
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Reststrahlen-method: Reststrahlen-method: measurements up to 50 measurements up to 50 m. m. Clear divergences from Clear divergences from Wien Wien distribution. distribution. (die (die Abweichungen lassen sich nicht Abweichungen lassen sich nicht wegdiskutieren)wegdiskutieren)
H. Rubens i F. Kurlbaum, Oct. H. Rubens i F. Kurlbaum, Oct. 19001900
Deviations from Deviations from Wien distributionWien distribution
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19 Oct. 19 Oct. 19001900
1exp
8),( 3
2
Tc
Tu
36
1exp
8),( 3
2
Tc
Tu
kh
h
/
TcTu
exp8
),( 3
3
WieWienn PlancPlanc
kk
Planck, 19 Oct. Planck, 19 Oct. 19001900
UUnn, dU, dUnn and and ΔΔUUnn are are not sufficient to not sufficient to calculate dScalculate dSnn
U is needed!U is needed!
UUS
2
2
)(2
2
UUUS
nUU
UUfndUUfUdUdS
n
nnnn
)()(
Feb. Feb. 19001900
M. Planck „Über eine Verbesserung der Wien’schen Spektralgleichung”, Verh. Deutsch. Phys. Gesell. 2 (1900) 202.
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«…at last I reached the point of constructing an absolutely arbitrary expressions for entropy which, though more complicated than the Wien’s expression, seems to satisfy with the same perfection every requirement of the thermodynamic and electromagnetic theories.»
Planck, 19 Oct. Planck, 19 Oct. 19001900
M. Planck „Über eine Verbesserung der Wien’schen Spektralgleichung”, Verh. Deutsch. Phys. Gesell. 2 (1900) 202.
)(2
2
UUUS
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Planck, 14 Dec. Planck, 14 Dec. 19001900
M. Planck „Zur Theorie des Gesetzes der Energieverteilung im Normalspectrum”, Verh. Deutsch. Phys. Gesell. 2 (1900) 237.
Discretization procedure
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Es wäre erhebend, wenn wir die Gehirnsubstanz auf eine Waage legen könnten, die von den theoretischen Physikern auf dem Altar dieser universellen Funktion hingeopfert wurde; und es ist dieses grausamen Opfers kein Ende abzusehen! Noch mehr: auch die klassische Mechanik fiel ihr zu Opfer, und es ist nicht abzusehen, ob. Maxwells Gleichungen der Elektrodynamik die Krisis überdauern werden, welche diese Funktion f
mit sich gebracht hat.
A. Einstein, 1913
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