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<!DOCTYPE article PUBLIC "-//NLM//DTD JATS (Z39.96) Journal Archiving and Interchange DTD with OASIS Tables with MathML3 v1.4 20241031//EN" "https://jats.nlm.nih.gov/archiving/1.4/JATS-archive-oasis-article1-4-mathml3.dtd">
<article xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:ali="http://www.niso.org/schemas/ali/1.0/" dtd-version="1.4" article-type="research-article" xml:lang="en"><front><journal-meta><journal-title-group><journal-title xml:lang="ru">Математическая физика и компьютерное моделирование</journal-title></journal-title-group><issn publication-format="print">2587-6325</issn><issn publication-format="electronic">2587-6902</issn></journal-meta><article-meta><article-id pub-id-type="doi">10.15688/mpcm.jvolsu.2024.3.4</article-id><article-categories><subj-group><subject>Other</subject></subj-group></article-categories><title-group><article-title xml:lang="ru">ПРИМЕНЕНИЕ СИСТЕМНОГО АНАЛИЗА И КОМПЬЮТЕРНЫХ АЛГОРИТМОВ ПРИ ИЗУЧЕНИИ ОРБИТ 7-МЕРНЫХ АЛГЕБР ЛИ</article-title><trans-title-group xml:lang="en"><trans-title>APPLICATION OF SYSTEMS ANALYSIS AND COMPUTER ALGORITHMS IN STUDYING ORBITS OF 7-DIMENSIONAL LIE ALGEBRAS</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author"><name-alternatives><name xml:lang="ru"><surname>Крутских</surname><given-names>Владислав Валерьевич</given-names></name><name xml:lang="en"><surname>Krutskikh</surname><given-names>Vladislav</given-names></name></name-alternatives><xref ref-type="aff" rid="aff1"/><email>krutskihvlad@mail.ru</email><contrib-id contrib-id-type="orcid">0009-0000-2670-1938</contrib-id></contrib><contrib contrib-type="author"><name-alternatives><name xml:lang="ru"><surname>Лобода</surname><given-names>Александр Васильевич</given-names></name><name xml:lang="en"><surname>Loboda</surname><given-names>Alexandr</given-names></name></name-alternatives><xref ref-type="aff" rid="aff2"/><email>lobvgasu@yandex.ru</email><contrib-id contrib-id-type="orcid">0000-0002-0285-5841</contrib-id></contrib><aff-alternatives id="aff1"><aff xml:lang="en"><institution>Voronezh State University  (Voronezh, Russian Federation)</institution></aff><aff xml:lang="ru"><institution>Воронежский государственный университет (Воронеж, Российская Федерация)</institution></aff></aff-alternatives><aff-alternatives id="aff2"><aff xml:lang="en"><institution>Voronezh State Technical University  (Voronezh, Russian Federation)</institution></aff><aff xml:lang="ru"><institution>Воронежский государственный технический университет (Воронеж, Российская Федерация)</institution></aff></aff-alternatives></contrib-group><pub-date pub-type="epub" iso-8601-date="2024-01-05"><day>05</day><month>01</month><year>2024</year></pub-date><volume>27</volume><issue>3</issue><fpage>38</fpage><lpage>59</lpage><history><date date-type="received" iso-8601-date="2024-08-10"><day>10</day><month>08</month><year>2024</year></date><date date-type="accepted" iso-8601-date="2024-09-18"><day>18</day><month>09</month><year>2024</year></date></history><permissions><license xlink:href="https://creativecommons.org/licenses/by/4.0/" xlink:title="CC BY 4.0"><ali:license_ref>https://creativecommons.org/licenses/by/4.0/</ali:license_ref><license-p xml:lang="ru">CC BY 4.0</license-p></license></permissions><abstract xml:lang="ru"><p>Обсуждается системный подход к задаче описания голо- морфно однородных вещественных гиперповерхностей пространства C4, каждая из которых является орбитой некоторой вещественной алгебры Ли. При изучении семейства 7-мерных алгебр Ли, играющего важную роль в поставленной задаче и содержащего более тысячи различных типов алгебр, является естественным использование компьютерных алгоритмов. С участием авторов данной статьи ранее были получены классификационные результаты об орбитах нескольких больших блоков алгебр из этого семейства. Установлены связи между наличием и размерностями нильпотентных и абелевых подалгебр исходных алгебр Ли и такими свойствами их орбит в C4, как вырожденность по Леви и трубчатость. В настоящей статье названные идеи и компьютерные алгоритмы применяются к семейству из 18 типов 7-мерных алгебр Ли, имеющих общий 6-мерный ниль-радикал. Построены голоморфные реализации в C4 этих алгебр и за счет их интегрирования получены все голоморфно однородные (в локальном смысле) невырожденные по Леви 7-мерные орбиты этого семейства. С использованием квадратичной замены переменных показано, что все эти орбиты голоморфно эквивалентны трубчатым гиперповерхностям.</p></abstract><abstract xml:lang="en" abstract-type="summary"><p>We discuss a systematic approach to the problem of describing holomorphically homogeneous real hypersurfaces in the space C4, each of which is an orbit of some real Lie algebra. When studying the family of 7-dimensional Lie algebras, which plays an important role in the problem at hand and contains more than a thousand different types of algebras, it is natural to use computer algorithms. With the participation of the authors of this article, classification results on the orbits of several large blocks of algebras from this family were previously obtained. Relations are established between the presence and dimensions of nilpotent and Abelian subalgebras of the original Lie algebras and such properties of their orbits in C4 as Levi degeneracy and tubularity. In this article, the above ideas and computer algorithms are applied to a family of 18 types of 7-dimensional Lie algebras that have a common 6-dimensional nil-radical. Holomorphic realizations in C4 of these algebras are constructed and by integrating them, all holomorphically homogeneous (in the local sense) Levi-nondegenerate 7-dimensional orbits of this family are obtained. Using a quadratic change of variables, it is shown that all these orbits are holomorphically equivalent to tubular hypersurfaces.</p></abstract><kwd-group xml:lang="ru"><kwd>абелева подалгебра</kwd><kwd>голоморфное преобразование</kwd><kwd>векторное поле</kwd><kwd>орбита алгебры</kwd><kwd>трубчатое многообразие</kwd><kwd>вещественная гиперповерхность</kwd><kwd>однородное многообразие</kwd><kwd>алгебра Ли</kwd></kwd-group><kwd-group xml:lang="en"><kwd>homogeneous manifold</kwd><kwd>Lie algebra</kwd><kwd>Abelian subalgebra</kwd><kwd>holomorphic transformation</kwd><kwd>vector field</kwd><kwd>orbit of an algebra</kwd><kwd>tubular manifold</kwd><kwd>real hypersurface</kwd></kwd-group></article-meta></front><back><ref-list><ref id="ref1"><mixed-citation publication-type="other" xml:lang="ru">Акимова, Е. В. Компьютерные алгоритмы интегрирования матричных алгебр Ли / Е. В. Акимова, А. В. 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