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<article article-type="research-article" dtd-version="1.3" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xml:lang="ru"><front><journal-meta><journal-id journal-id-type="publisher-id">cheb</journal-id><journal-title-group><journal-title xml:lang="ru">Чебышевский сборник</journal-title><trans-title-group xml:lang="en"><trans-title>Chebyshevskii Sbornik</trans-title></trans-title-group></journal-title-group><issn pub-type="ppub">2226-8383</issn><publisher><publisher-name>Tula State Lev Tolstoy  Pedagogical University</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="doi">10.22405/2226-8383-2022-23-1-209-222</article-id><article-id custom-type="elpub" pub-id-type="custom">cheb-1244</article-id><article-categories><subj-group subj-group-type="heading"><subject>Research Article</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="ru"><subject>История математики и приложений</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="en"><subject>Сomputer science</subject></subj-group></article-categories><title-group><article-title>О теореме Пуанкаре — Биркгофа как важнейшем результате теории динамических систем</article-title><trans-title-group xml:lang="en"><trans-title>On the Poincar´e-Birkhoff theorem as the important result of the theory of dynamical systems</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Мухин</surname><given-names>Равиль Рафкатович</given-names></name><name name-style="western" xml:lang="en"><surname>Mukhin</surname><given-names>Ravil’ Rafkatovich</given-names></name></name-alternatives><bio xml:lang="ru"><p>доктор физико-математических наук</p></bio><bio xml:lang="en"><p>doctor of physical and mathematical sciences</p></bio><email xlink:type="simple">mukhiny@mail.ru</email><xref ref-type="aff" rid="aff-1"/></contrib></contrib-group><aff-alternatives id="aff-1"><aff xml:lang="ru"><institution>Старооскольский технологический институт им. А. А. Угарова; филиал Национального исследовательского технологического университета «МИСиС»</institution><country>Россия</country></aff><aff xml:lang="en"><institution>Stary Oskol Technological Institute of National Research University of Science and Technology “MISiS”</institution><country>Russian Federation</country></aff></aff-alternatives><pub-date pub-type="collection"><year>2022</year></pub-date><pub-date pub-type="epub"><day>06</day><month>06</month><year>2022</year></pub-date><volume>23</volume><issue>1</issue><fpage>209</fpage><lpage>222</lpage><permissions><copyright-statement>Copyright &amp;#x00A9; Мухин Р.Р., 2022</copyright-statement><copyright-year>2022</copyright-year><copyright-holder xml:lang="ru">Мухин Р.Р.</copyright-holder><copyright-holder xml:lang="en">Mukhin R.R.</copyright-holder><license xml:lang="ru" license-type="creative-commons-attribution" xlink:href="https://creativecommons.org/licenses/by/4.0/" xlink:type="simple"><license-p>Данная работа распространяется под лицензией Creative Commons Attribution 4.0.</license-p></license><license xml:lang="en" license-type="creative-commons-attribution" xlink:href="https://creativecommons.org/licenses/by/4.0/" xlink:type="simple"><license-p>This work is licensed under a Creative Commons Attribution 4.0 License.</license-p></license></permissions><self-uri xlink:href="https://www.chebsbornik.ru/jour/article/view/1244">https://www.chebsbornik.ru/jour/article/view/1244</self-uri><abstract><p>Целью работы является изучение истории теоремы Пуанкаре — Биркгофа, которая является не только одним из результатов, лежащих в основе теории динамических систем, но имеет важное значение для приложений. До настоящего времени теорема Пуанкаре — Биркгофа рассматривалась в историческом плане лишь фрагментарно и не являлась предметом последовательного исторического исследования. Исследование основано на анализе оригинальных работ, историко-научной литературы с привлечением воспоминаний участников описываемых событий. Идея Пуанкаре заключалась в установлении периодических движений динамических систем с помощью предложенной им геометрической теоремы.Периодические движения, в свою очередь, должны были послужить основой для изучения других, сложных движений. Поиски доказательства явились мощным импульсом для Биркгофа в построении теории динамических систем, который вместе с Пуанкаре является основателем этой области математики. Теорема Пуанкаре — Биркгофа имеет ключевое значение в понимании механизма возникновения хаотического движения в гамильтоновых системах. История теоремы Пуанкаре — Биркгофа не закончена, она играет значительную роль в современной теории динамических систем и ее приложениях. Продолжаются поиски доказательства многомерного аналога теоремы, ее различных обобщений и дальнейших приложений.</p></abstract><trans-abstract xml:lang="en"><p>The aim of this work is to study the history of the Poincar´e-Birkhoff theorem, which is not only one of the results underlying the theory of dynamical systems, but is important for applications. Until now, the Poincar´e-Birkhoff theorem has been considered historically only fragmentarily and has not been the subject of consistent historical research. The research is based on the analysis of original works, historical and scientific literature, involving the recollections of participants in the described events. Poincar´e’s idea was to establish the periodic motions of dynamical systems using the geometric theorem he proposed. Periodic movements, in turn, were supposed to serve as a basis for studying other, complex movements. The search for a proof was a powerful impetus for Birkhoff in the construction of the theory of dynamical systems, who, together with Poincar´e, is the founder of this area of mathematics. Poincar´e- Birkhoff theorem is of key importance in understanding the mechanism of the onset of chaotic motion in Hamiltonian systems. The history of the Poincar´e-Birkhoff theorem is not complete;it plays a significant role in the modern theory of dynamical systems and its applications.The search continues for a proof of a multidimensional analogue of the theorem, its various generalizations, and further applications.</p></trans-abstract><kwd-group xml:lang="ru"><kwd>интегрирование дифференциальных уравнений</kwd><kwd>проблема трех тел</kwd><kwd>динамическая система</kwd><kwd>периодические движения</kwd><kwd>хаотические движения.</kwd></kwd-group><kwd-group xml:lang="en"><kwd>integration of differential equations</kwd><kwd>three-body problem</kwd><kwd>dynamical system</kwd><kwd>periodic motions</kwd><kwd>chaotic motions.</kwd></kwd-group><funding-group><funding-statement xml:lang="ru">Работа выполнена при поддержке РФФИ (проект 20-011-00402 А)</funding-statement><funding-statement xml:lang="en">Thе work was supported by the RFBR, project No. 20-011-00402 A</funding-statement></funding-group></article-meta></front><back><ref-list><title>References</title><ref id="cit1"><label>1</label><citation-alternatives><mixed-citation xml:lang="ru">Пуанкаре A. 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