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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">mais</journal-id><journal-title-group><journal-title xml:lang="ru">Моделирование и анализ информационных систем</journal-title><trans-title-group xml:lang="en"><trans-title>Modeling and Analysis of Information Systems</trans-title></trans-title-group></journal-title-group><issn pub-type="ppub">1818-1015</issn><issn pub-type="epub">2313-5417</issn><publisher><publisher-name>Yaroslavl State University</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="doi">10.18255/1818-1015-2014-4-35-46</article-id><article-id custom-type="elpub" pub-id-type="custom">mais-96</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>Оригинальные статьи</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="en"><subject>Articles</subject></subj-group></article-categories><title-group><article-title>О пространстве путей на полных пересечениях в грассманианах</article-title><trans-title-group xml:lang="en"><trans-title>On the Variety of Paths on Complete Intersections in Grassmannians</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>Ермакова</surname><given-names>Светлана Михайловна</given-names></name><name name-style="western" xml:lang="en"><surname>Yermakova</surname><given-names>S. M.</given-names></name></name-alternatives><bio xml:lang="ru"><p>ассистент кафедры общей математики, 150000 Россия, г. Ярославль, ул. Советская, 14</p></bio><bio xml:lang="en"><p>ассистент кафедры общей математики, Sovetskaya str., 14, Yaroslavl, 150000, Russia</p></bio><email xlink:type="simple">svetlana.ermakova1802@gmail.com</email><xref ref-type="aff" rid="aff-1"/></contrib></contrib-group><aff-alternatives id="aff-1"><aff xml:lang="ru"><institution>Ярославский государственный университет им. П.Г. Демидова</institution><country>Россия</country></aff><aff xml:lang="en"><institution>P.G. Demidov Yaroslavl State University</institution><country>Russian Federation</country></aff></aff-alternatives><pub-date pub-type="collection"><year>2014</year></pub-date><pub-date pub-type="epub"><day>20</day><month>08</month><year>2014</year></pub-date><volume>21</volume><issue>4</issue><fpage>35</fpage><lpage>46</lpage><permissions><copyright-statement>Copyright &amp;#x00A9; Ермакова С.М., 2014</copyright-statement><copyright-year>2014</copyright-year><copyright-holder xml:lang="ru">Ермакова С.М.</copyright-holder><copyright-holder xml:lang="en">Yermakova S.M.</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.mais-journal.ru/jour/article/view/96">https://www.mais-journal.ru/jour/article/view/96</self-uri><abstract><p>В данной работе мы изучаем многообразие Фано прямых на полном пересечении грассманиана G(n, 2n) с гиперповерхностями степени d1, ..., ds. Путем длины l на таком многообразии мы называем связную кривую, состоящую из l прямых. Главным результатом работы является факт, что при 2 ∑i (di+1) ≤ [n/2] пространство путей длины n, соединяющих любые две точки полного пересечения, связно и непусто. Для доказательства этого результата мы показываем, что на грассманиане G(n, 2n) пространство путей длины n, соединяющих две общие точки, изоморфно прямому произведению Fn × Fn двух полных пространств n-мерных флагов. Затем строим на Fn ×Fn глобально порожденное векторное расслоение E с выделенным сечением s, таким что нули s задают пространство путей длины n, соединяющих x и y и лежащих в пересечении гиперповерхностей степеней d1,...,dk. Используя явное представление расслоения E в виде прямой суммы линейных, мы показываем, что нули общего, а следовательно, и любого сечения E образуют непустое, связное подмногообразие в Fn × Fn.</p><p>Помимо геометрического интереса, ценность доказанного результата состоит в том, что мы используем его в будущих работах для обобщения теорем о расщепимости расслоений конечного ранга на инд-многообразиях.</p><p> </p></abstract><trans-abstract xml:lang="en"><p>In this article we study the Fano variety of lines on the complete intersection of the grassmannian G(n, 2n) with hypersurfaces of degrees d1 ..., di . A length l path on such a variety is a connected curve composed of l lines. The main result of this article states that the space of length l paths connecting any two given points on the variety is nonempty and connected if ∑dj &lt; n/4 . To prove this result we first show that the space of length n paths on the grassmannian G(n, 2n) that join two generic points is isomorphic to the direct product Fn ×Fn of spaces of full flags. After this we construct on Fn ×Fn a globally generated vector bundle E with a distinguished section s such that the zeros of s coincide with the space of length n paths that join x and y and lie in the intersection of hypersurfaces of degrees d1,...,dk. Using a presentation of E as a sum of linear bundles we show that zeros of its generic and, hence, any section form a non empty connected subvariety of Fn × Fn. Apart from its immediate geometric interest, this result will be used in our future work on generalisation of splitting theorems for finite rank vector bundles on ind-manifolds.</p></trans-abstract><kwd-group xml:lang="ru"><kwd>грассманиан</kwd><kwd>векторное расслоение</kwd><kwd>многообразие Фано прямых</kwd></kwd-group><kwd-group xml:lang="en"><kwd>grassmannian</kwd><kwd>vector bundle</kwd><kwd>Fano variety of lines</kwd></kwd-group></article-meta></front><back><ref-list><title>References</title><ref id="cit1"><label>1</label><citation-alternatives><mixed-citation xml:lang="ru">Eisenbud D., Harris J. 3264 &amp; All That Intersection. Theory in Algebraic Geometry. 2013. URL: http://isites.harvard.edu/fs/docs/icb.topic720403.files/book.pdf.</mixed-citation><mixed-citation xml:lang="en">Eisenbud D., Harris J. 3264 &amp; All That Intersection. Theory in Algebraic Geometry. 2013. URL: http://isites.harvard.edu/fs/docs/icb.topic720403.files/book.pdf.</mixed-citation></citation-alternatives></ref><ref id="cit2"><label>2</label><citation-alternatives><mixed-citation xml:lang="ru">Barth W., Van de Ven A. On the geometry in codimension 2 in Grassmann manifolds // Lecture Notes in Math. 412. Springer-Verlag, 1974. P. 1–35.</mixed-citation><mixed-citation xml:lang="en">Barth W., Van de Ven A. On the geometry in codimension 2 in Grassmann manifolds // Lecture Notes in Math. 412. Springer-Verlag, 1974. P. 1–35.</mixed-citation></citation-alternatives></ref><ref id="cit3"><label>3</label><citation-alternatives><mixed-citation xml:lang="ru">Tyurin A. N. Vector bundles of finite rank over infinite varieties // Math. USSR. Izvestija. 1976. No 10. P. 1187–1204.</mixed-citation><mixed-citation xml:lang="en">Tyurin A. N. Vector bundles of finite rank over infinite varieties // Math. USSR. Izvestija. 1976. No 10. P. 1187–1204.</mixed-citation></citation-alternatives></ref><ref id="cit4"><label>4</label><citation-alternatives><mixed-citation xml:lang="ru">Sato E. On the decomposability of infinitely extendable vector bundles on projective spaces and Grassmann varieties // J. Math. Kyoto Univ. 1977. No 17. P. 127–150.</mixed-citation><mixed-citation xml:lang="en">Sato E. On the decomposability of infinitely extendable vector bundles on projective spaces and Grassmann varieties // J. Math. Kyoto Univ. 1977. No 17. P. 127–150.</mixed-citation></citation-alternatives></ref><ref id="cit5"><label>5</label><citation-alternatives><mixed-citation xml:lang="ru">Donin J., Penkov I. Finite rank vector bundles on inductive limits of grassmannians // IMRN. 2003. No 34. P. 1871–1887.</mixed-citation><mixed-citation xml:lang="en">Donin J., Penkov I. Finite rank vector bundles on inductive limits of grassmannians // IMRN. 2003. No 34. P. 1871–1887.</mixed-citation></citation-alternatives></ref><ref id="cit6"><label>6</label><citation-alternatives><mixed-citation xml:lang="ru">Penkov I., Tikhomirov A. S. Rank-2 vector bundles on ind-Grassmannians // Algebra, arithmetic, and geometry: in honor of Yu. I. Manin, V II, Progr. Math. V. 270. Birkhaeuser, Boston-Basel-Berlin, 2009. P. 555–572.</mixed-citation><mixed-citation xml:lang="en">Penkov I., Tikhomirov A. S. Rank-2 vector bundles on ind-Grassmannians // Algebra, arithmetic, and geometry: in honor of Yu. I. Manin, V II, Progr. Math. V. 270. Birkhaeuser, Boston-Basel-Berlin, 2009. P. 555–572.</mixed-citation></citation-alternatives></ref><ref id="cit7"><label>7</label><citation-alternatives><mixed-citation xml:lang="ru">Пенков И.Б., Тихомиров А.С. Тривиальность векторных расслоений на скрученных инд-грассманианах // Математический сборник. 2011. 202. No 1. С. 65–104 (English translation: Penkov I.B., Tikhomirov A.S. Triviality of vector bundles on twisted indGrassmannians // Sbornik: Mathematics. 2011. 202, No 1. P. 61–99).</mixed-citation><mixed-citation xml:lang="en">Пенков И.Б., Тихомиров А.С. Тривиальность векторных расслоений на скрученных инд-грассманианах // Математический сборник. 2011. 202. No 1. С. 65–104 (English translation: Penkov I.B., Tikhomirov A.S. Triviality of vector bundles on twisted indGrassmannians // Sbornik: Mathematics. 2011. 202, No 1. P. 61–99).</mixed-citation></citation-alternatives></ref><ref id="cit8"><label>8</label><citation-alternatives><mixed-citation xml:lang="ru">Penkov I., Tikhomirov A.S. On the Barth–Van de Ven–Tyurin–Sato theorem // arXiv:1405.3897 math.AG].</mixed-citation><mixed-citation xml:lang="en">Penkov I., Tikhomirov A.S. On the Barth–Van de Ven–Tyurin–Sato theorem // arXiv:1405.3897 math.AG].</mixed-citation></citation-alternatives></ref><ref id="cit9"><label>9</label><citation-alternatives><mixed-citation xml:lang="ru">Penkov I., Tikhomirov A.S. Linear ind-grassmannians // Pure and Applied Mathematics Quarterly. 2014. 10. Nо 1. arXiv: 1310.8058 [math.AG].</mixed-citation><mixed-citation xml:lang="en">Penkov I., Tikhomirov A.S. Linear ind-grassmannians // Pure and Applied Mathematics Quarterly. 2014. 10. Nо 1. arXiv: 1310.8058 [math.AG].</mixed-citation></citation-alternatives></ref><ref id="cit10"><label>10</label><citation-alternatives><mixed-citation xml:lang="ru">Hartshorne R. Algebraic Geometry. New York: Springer-Verlag, 1977.</mixed-citation><mixed-citation xml:lang="en">Hartshorne R. Algebraic Geometry. New York: Springer-Verlag, 1977.</mixed-citation></citation-alternatives></ref></ref-list><fn-group><fn fn-type="conflict"><p>The authors declare that there are no conflicts of interest present.</p></fn></fn-group></back></article>
