{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,7]],"date-time":"2026-10-07T15:04:57Z","timestamp":1791385497250,"version":"4.3.3"},"reference-count":15,"publisher":"Wiley","license":[{"start":{"date-parts":[[2026,10,7]],"date-time":"2026-10-07T00:00:00Z","timestamp":1791331200000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"},{"start":{"date-parts":[[2026,10,7]],"date-time":"2026-10-07T00:00:00Z","timestamp":1791331200000},"content-version":"tdm","delay-in-days":0,"URL":"http:\/\/doi.wiley.com\/10.1002\/tdm_license_1.1"}],"funder":[{"DOI":"10.13039\/501100002428","name":"Austrian Science Fund","doi-asserted-by":"publisher","award":["P34783"],"award-info":[{"award-number":["P34783"]}],"id":[{"id":"10.13039\/501100002428","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100005788","name":"Medizinische Universit\u00e4t Wien","doi-asserted-by":"publisher","id":[{"id":"10.13039\/501100005788","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["onlinelibrary.wiley.com"],"crossmark-restriction":true},"short-container-title":["Journal of Microscopy"],"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>In 1922, L\u00e9on Brillouin introduced the idea of light scattering from thermal fluctuations, in a paper titled: \u2018Diffusion de la lumi\u00e8re et des rayons X par un corps transparent et homog\u00e9ne, influence de l'agitation thermique\u2019. Brillouin's mathematical treatment elegantly unifies principles from thermodynamics, optics and electromagnetic theory (as they were understood at the time) to arrive at a set of equations\u00a0describing the scattering process, in a form that is still in use today. The effect he describes became known as Brillouin scattering, and was experimentally verified in 1930. It would go on to become the underlying principle of novel sensing and lasing technologies, as well as more recently also Brillouin microscopy. Despite the elegant derivation presented by Brillouin, and its scientific significance, the original French manuscript is rarely studied by the scientific community. With English serving as the lingua franca of our time, doing so is understandably challenging for the broader research community. While the original manuscript presents coherent and well\u2010founded theoretical derivations, following the thought process of the author, from a direct literal translation of the article can be somewhat challenging. The paper uses dated notations, some less common mathematical transformations, and in some cases seemingly unjustified physical simplifications. It also on occasion changes symbols for a quantity half way through, and there are several typographical errors that might confuse readers not intimately familiar with his line of argument. Here we provide an English translation of the original manuscript, with modernized notations and corrections, together with a supplementary text in which we discuss the derivation of each of the equations, along with the assumptions used in obtaining them. Our hope is that by providing the literal translation together with the accompanying discussion, we can transform this document from a blindly cited historical artefact to an accessible pedagogical tool that provides insight into the scientific development and discussions in the\u00a01920's.<\/jats:p>","DOI":"10.1111\/jmi.70176","type":"journal-article","created":{"date-parts":[[2026,10,7]],"date-time":"2026-10-07T14:49:12Z","timestamp":1791384552000},"update-policy":"https:\/\/doi.org\/10.1002\/crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Translation and discussion of Leon Brillouin's 1922 paper titled:\n                    <i>Diffusion of light and X\u2010rays by a transparent homogeneous body: Influence of thermal agitation<\/i>"],"prefix":"10.1111","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-8450-0106","authenticated-orcid":false,"given":"Pierre","family":"Bouvet","sequence":"first","affiliation":[{"name":"Division of Anatomy, Center for Anatomy and Cell Biology Medical University of Vienna Vienna Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1642-2905","authenticated-orcid":false,"given":"Kareem","family":"Elsayad","sequence":"additional","affiliation":[{"name":"Division of Anatomy, Center for Anatomy and Cell Biology Medical University of Vienna Vienna Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"311","published-online":{"date-parts":[[2026,10,7]]},"reference":[{"issue":"2","key":"e_1_2_4_2_1","doi-asserted-by":"crossref","first-page":"205","DOI":"10.1002\/andp.19083300203","article-title":"Molekular\u2010kinetische Theorie der Opaleszenz von Gasen im kritischen Zustande, sowie einiger verwandter Erscheinungen","volume":"330","author":"Smoluchowski M.","year":"1908","journal-title":"Annalen der Physik"},{"issue":"1761","key":"e_1_2_4_3_1","doi-asserted-by":"crossref","first-page":"289","DOI":"10.1038\/068289a0","article-title":"Scientific papers of Lord Rayleigh","volume":"68","author":"Rayleigh L.","year":"1903","journal-title":"Nature"},{"key":"e_1_2_4_4_1","first-page":"62","article-title":"Sur la diffusion de la lumi\u00e8re par l'air","volume":"160","author":"Cabannes J.","year":"1915","journal-title":"Comptes rendus de l'Acad\u00e9mie des Sciences"},{"issue":"5","key":"e_1_2_4_5_1","doi-asserted-by":"crossref","first-page":"129","DOI":"10.1051\/jphysrad:0192000105012900","article-title":"Relation entre le degr\u00e9 de polarisation et l'intensit\u00e9 de la lumi\u00e8re diffus\u00e9e par des mol\u00e9cules anisotropes. Nouvelle d\u00e9termination de la constante d'Avogadro","volume":"1","author":"Cabannes J.","year":"1920","journal-title":"Journal de Physique et le Radium"},{"key":"e_1_2_4_6_1","doi-asserted-by":"crossref","unstructured":"Cabannes J.(1921).Sur la diffusion de la lumi\u00e8re par les mol\u00e9cules des gaz transparents[Doctoral dissertation Universit\u00e9 de Paris]. Masson.","DOI":"10.1051\/anphys\/192109150005"},{"issue":"662","key":"e_1_2_4_7_1","first-page":"453","article-title":"Scattering of light by dust\u2010free air, with artificial reproduction of the blue sky\u2014Preliminary note","volume":"94","author":"Strutt R. J.","year":"1918","journal-title":"Proceedings of the Royal Society of London. Series A"},{"key":"e_1_2_4_8_1","unstructured":"Smoluchowski M.(1916).Experimentell nachweisbare der \u00fcblichen Thermodynamik widersprechende Molekularph\u00e4nomene.Bulletin International de l'Acad\u00e9mie des Sciences de Cracovie Classe des sciences math\u00e9matiques et naturelles 218\u2013222."},{"key":"e_1_2_4_9_1","doi-asserted-by":"crossref","first-page":"1275","DOI":"10.1002\/andp.19103381612","article-title":"Theorie der Opaleszenz von homogenen Fl\u00fcssigkeiten und Fl\u00fcssigkeitsgemischen in der N\u00e4he des kritischen Zustandes","volume":"33","author":"Einstein A.","year":"1910","journal-title":"Annalen der Physik"},{"key":"e_1_2_4_10_1","first-page":"1331","article-title":"Diffusion de la lumi\u00e8re par un corps transparent homog\u00e8ne","volume":"158","author":"Brillouin L.","year":"1914","journal-title":"Comptes Rendus Hebdomadaires des S\u00e9ances de l'Acad\u00e9mie des Sciences"},{"issue":"14","key":"e_1_2_4_11_1","doi-asserted-by":"crossref","first-page":"789","DOI":"10.1002\/andp.19123441404","article-title":"Zur Theorie der spezifischen W\u00e4rmen","volume":"344","author":"Debye P.","year":"1912","journal-title":"Annalen der Physik"},{"key":"e_1_2_4_12_1","doi-asserted-by":"crossref","first-page":"357","DOI":"10.24033\/asens.727","article-title":"La th\u00e9orie des solides et les quanta","volume":"37","author":"Brillouin L.","year":"1920","journal-title":"Annales scientifiques de l'\u00c9cole Normale Sup\u00e9rieure"},{"key":"e_1_2_4_13_1","first-page":"317","article-title":"Eine neue Interferenzerscheinung bei R\u00f6nlgenstrahlen","volume":"14","author":"Friedrich W.","year":"1913","journal-title":"Physikalische Zeitschrift"},{"key":"e_1_2_4_14_1","first-page":"277","article-title":"Interferenzen an regellos orientierten Teilchen im R\u00f6ntgenlicht (Teil I)","volume":"17","author":"Debye P.","year":"1916","journal-title":"Physikalische Zeitschrift"},{"key":"e_1_2_4_15_1","first-page":"291","article-title":"Interferenzen an regellos orientierten Teilchen im R\u00f6ntgenlicht (Teil III)","volume":"18","author":"Debye P.","year":"1917","journal-title":"Physikalische Zeitschrift"},{"issue":"1","key":"e_1_2_4_16_1","doi-asserted-by":"crossref","first-page":"49","DOI":"10.1002\/andp.19133480105","article-title":"Interferenz von Roentgenstrahlen und Waermebewegung","volume":"348","author":"Debye P.","year":"1914","journal-title":"Annalen der Physik"}],"container-title":["Journal of Microscopy"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/pdf\/10.1111\/jmi.70176","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/full-xml\/10.1111\/jmi.70176","content-type":"application\/xml","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/pdf\/10.1111\/jmi.70176","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,10,7]],"date-time":"2026-10-07T14:49:15Z","timestamp":1791384555000},"score":1,"resource":{"primary":{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/10.1111\/jmi.70176"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,10,7]]},"references-count":15,"alternative-id":["10.1111\/jmi.70176"],"URL":"https:\/\/doi.org\/10.1111\/jmi.70176","archive":["Portico"],"relation":{},"ISSN":["0022-2720","1365-2818"],"issn-type":[{"value":"0022-2720","type":"print"},{"value":"1365-2818","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,10,7]]},"assertion":[{"value":"2026-07-17","order":0,"name":"received","label":"Received","group":{"name":"publication_history","label":"Publication History"}},{"value":"2026-09-15","order":2,"name":"accepted","label":"Accepted","group":{"name":"publication_history","label":"Publication History"}},{"value":"2026-10-07","order":3,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}],"article-number":"jmi.70176"}}