Editing Timeline of thermodynamics (section)

== 1900–1944 ==
* 1900&nbsp;– [[Max Planck]] suggests that light may be emitted in discrete frequencies, giving his [[Planck's law of black-body radiation|law of black-body radiation]]<ref>{{Cite book|last=Planck, Max, 1858-1947.|url=http://worldcat.org/oclc/15745309|title=Zur Theorie des Gesetzes der Energieverteilung im Normalspectrum|oclc=15745309}}</ref>
* 1905&nbsp;– [[Albert Einstein]], in the first of his [[Annus Mirabilis papers|miracle year papers]], argues that the reality of [[quantum|quanta]] would explain the [[photoelectric effect]]<ref>{{Cite journal|last=Einstein|first=Albert|date=1905|title=On a Heuristic Viewpoint Concerning the Production and Transformation of Light|url=https://www.pitt.edu/~jdnorton/lectures/Rotman_Summer_School_2013/Einstein_1905_docs/Einstein_Light_Quantum_WikiSource.pdf|journal=Annalen der Physik (In German)}}</ref>
* 1905&nbsp;– Einstein mathematically analyzes [[Brownian motion]] as a result of random molecular motion in his paper [[Über die von der molekularkinetischen Theorie der Wärme geforderte Bewegung von in ruhenden Flüssigkeiten suspendierten Teilchen|On the movement of small particles suspended in a stationary liquid demanded by the molecular-kinetic theory of heat]]
* 1906&nbsp;– Nernst presents a formulation of the [[third law of thermodynamics]]
* 1907&nbsp;– Einstein uses quantum theory to estimate the [[heat capacity]] of an [[Einstein solid]]
* 1909&nbsp;– [[Constantin Carathéodory]] develops an [[axiomatic system]] of thermodynamics <ref>{{cite journal |last1=Pogliani |first1=Lionello |last2=Berberan-Santos |first2=Mario |title=Constantin Carathéodory and the axiomatic thermodynamics |journal=Journal of Mathematical Chemistry |date=2000 |volume=28 |issue=1 |page=313 |doi=10.1023/A:1018834326958 |s2cid=17244147 |url=https://link-springer-com.huaryu.kl.oakland.edu/content/pdf/10.1023/A:1018834326958.pdf |access-date=May 30, 2022}}</ref>
* 1910&nbsp;– Einstein and [[Marian Smoluchowski]] find the [[Einstein–Smoluchowski formula]] for the attenuation coefficient due to density fluctuations in a gas
* 1911&nbsp;– [[Paul Ehrenfest]] and [[Tatyana Afanasyeva|Tatjana Ehrenfest–Afanassjewa]] publish their classical review on the statistical mechanics of Boltzmann, ''Begriffliche Grundlagen der statistischen Auffassung in der Mechanik''
* 1912&nbsp;– [[Peter Debye]] gives an [[Debye model|improved heat capacity estimate]] by allowing low-frequency [[phonons]]<ref>{{cite journal |first=Peter |last=Debye |title=Zur Theorie der spezifischen Waerme  |language=de|journal=[[Annalen der Physik]] |volume=39 |issue=4 |pages=789–839 |year=1912 |doi= 10.1002/andp.19123441404 |bibcode = 1912AnP...344..789D |url=https://zenodo.org/record/1424256 }}</ref>
* 1916&nbsp;– [[Sydney Chapman (mathematician)|Sydney Chapman]] and [[David Enskog]] systematically develop the kinetic theory of gases
* 1916&nbsp;– Einstein considers the thermodynamics of [[atomic spectral line]]s and predicts [[stimulated emission]]
* 1919&nbsp;– [[James Jeans]] discovers that the dynamical constants of motion determine the distribution function for a system of particles
* 1920&nbsp;– [[Meghnad Saha]] states his [[Saha ionization equation|ionization equation]]<ref>{{cite journal|doi=10.1080/14786441008636148|title=LIII.Ionization in the solar chromosphere|year=1920|last1=Saha|first1=Megh Nad|journal=Philosophical Magazine |series=Series 6|volume=40|issue=238|pages=472–488|url=https://zenodo.org/record/1430870}}</ref>
* 1923&nbsp;– Debye and [[Erich Hückel]] publish a statistical treatment of the dissociation of [[electrolyte]]s
* 1924&nbsp;– [[Satyendra Nath Bose]] introduces [[Bose–Einstein statistics]], in a paper translated by Einstein
* 1926&nbsp;– [[Enrico Fermi]]<ref name='Fermi1926'>{{cite journal| title=Sulla quantizzazione del gas perfetto monoatomico| journal=Rendiconti Lincei| language=it| year=1926| first=Enrico| last=Fermi| volume=3| pages=145–9}}, translated as {{cite arXiv| title=On the Quantization of the Monoatomic Ideal Gas| eprint=cond-mat/9912229| date=1999-12-14 | last1=Zannoni| first1=Alberto}}</ref> and [[Paul Dirac]]<ref name='Dirac1926'>{{cite journal| title=On the Theory of Quantum Mechanics| journal=Proceedings of the Royal Society A| year=1926| first=Paul A. M.| last=Dirac| author-link=Paul Dirac| volume=112| issue=762| pages=661–77| jstor=94692| doi=10.1098/rspa.1926.0133 |bibcode = 1926RSPSA.112..661D | doi-access=free}}</ref> introduce [[Fermi–Dirac statistics]]
* 1927&nbsp;– [[John von Neumann]] introduces the [[density matrix]] representation,<ref>{{Citation | last = von Neumann | first = John  | year = 1927 | author-link = John von Neumann  |title=Wahrscheinlichkeitstheoretischer Aufbau der Quantenmechanik | journal = Göttinger Nachrichten | volume = 1|pages= 245–272|url=https://eudml.org/doc/59230}}</ref> establishing [[quantum statistical mechanics]]
* 1928&nbsp;– [[John Bertrand Johnson|John B. Johnson]] discovers [[Johnson noise]] in a resistor <ref>{{Cite journal |doi = 10.1103/PhysRev.29.350|title = Minutes of the Philadelphia Meeting December 28, 29, 30, 1926|journal = Physical Review|volume = 29|issue = 2|pages = 350–373|year = 1927|last1 = Anonymous|bibcode = 1927PhRv...29..350.}}</ref><ref>{{cite journal|first=J.|last=Johnson|title=Thermal Agitation of Electricity in Conductors|journal= Physical Review|volume=32|pages=97–109|number=97|date=1928|doi=10.1103/physrev.32.97|bibcode=1928PhRv...32...97J}}</ref>
* 1928&nbsp;– [[Harry Nyquist]] derives the [[fluctuation-dissipation theorem]], a relationship to explain [[Johnson noise]] in a resistor <ref>{{cite journal | author = Nyquist H |author-link = Harry Nyquist | year = 1928 | title = Thermal Agitation of Electric Charge in Conductors | journal = [[Physical Review]] | volume = 32 |issue = 1 | pages = 110&ndash;113 | bibcode = 1928PhRv...32..110N | doi = 10.1103/PhysRev.32.110 }}</ref>
* 1931&nbsp;– [[Lars Onsager]] publishes his groundbreaking paper deriving the [[Onsager reciprocal relations]]<ref name="onsager">{{cite journal | last=Onsager | first=Lars | title=Reciprocal Relations in Irreversible Processes. I. | journal=Physical Review | publisher=American Physical Society (APS) | volume=37 | issue=4 | date=1931-02-15 | issn=0031-899X | doi=10.1103/physrev.37.405 | pages=405–426| bibcode=1931PhRv...37..405O |doi-access=free}}</ref>
* 1935&nbsp;– [[Ralph H. Fowler]] invents the title '[[Zeroth law of thermodynamics|the zeroth law of thermodynamics]]' to summarise postulates made by earlier physicists that thermal equilibrium between systems is a [[transitive relation]]
* 1938&nbsp;– [[Anatoly Vlasov]] proposes the [[Vlasov equation]] for a correct dynamical description of ensembles of particles with collective long range interaction<ref>{{cite journal|author=A. A. Vlasov|title=On Vibration Properties of Electron Gas|journal=[[Journal of Experimental and Theoretical Physics|J. Exp. Theor. Phys.]]|volume=8|pages=291|date=1938|url= http://ufn.ru/ru/articles/1967/11/f/|language=ru|issue=3}}</ref><ref>{{cite journal|author=A. A. Vlasov|title=The Vibrational Properties of an Electron Gas|journal=Soviet Physics Uspekhi| volume=10| pages=721–733|date=1968|url= http://www.iop.org/EJ/abstract/0038-5670/10/6/R01|doi=10.1070/PU1968v010n06ABEH003709|issue=6|bibcode = 1968SvPhU..10..721V |s2cid=122952713 }}</ref>
* 1939&nbsp;– [[Nikolay Mitrofanovich Krylov|Nikolay Krylov]] and [[Nikolay Bogolyubov]] give the first consistent microscopic derivation of the [[Fokker–Planck equation]] in the single scheme of classical and quantum mechanics <ref>[[Nikolay Boglyubov Jr.|N. N. Bogolyubov Jr.]] and D. P. Sankovich (1994). "N. N. Bogolyubov and statistical mechanics". ''Russian Math. Surveys'' '''49'''(5): 19—49. {{doi|10.1070/RM1994v049n05ABEH002419}}</ref><ref>[[Nikolay Bogoliubov|N. N. Bogoliubov]] and [[Nikolay Mitrofanovich Krylov|N. M. Krylov]] (1939). ''Fokker–Planck equations generated in perturbation theory by a method based on the spectral properties of a perturbed Hamiltonian''. Zapiski Kafedry Fiziki Akademii Nauk Ukrainian SSR '''4''': 81–157 (in Ukrainian).</ref>
* 1942&nbsp;– [[Joseph L. Doob]] states his theorem on [[Gauss–Markov process]]es
* 1944&nbsp;– [[Lars Onsager]] gives an analytic solution to the 2-dimensional [[Ising model]], including its [[phase transition]]<ref>{{Cite journal|last=Onsager|first=Lars|date=1944-02-01|title=Crystal Statistics. I. A Two-Dimensional Model with an Order-Disorder Transition|url=http://dx.doi.org/10.1103/physrev.65.117|journal=Physical Review|volume=65|issue=3–4|pages=117–149|doi=10.1103/physrev.65.117|bibcode=1944PhRv...65..117O|issn=0031-899X}}</ref>