On the Geometry of Almost Quasi-Para-Sasakian Manifolds Equipped with a Canonical N-Connection

УДК 514.763

  • S.V. Galaev Saratov State University (Saratov, Russiа) Email: sgalaev@mail.ru
  • E.A. Kokin Saratov State University (Saratov, Russiа) Email: evgeny@epromicro.com
Keywords: аlmost quasi-para-Sasakian manifold, intrinsic connection, extended skew-symmetric connection, η-Einstein manifold

Abstract

This paper introduces the concept of an almost quasi-para-Sasakian manifold, which differs from the previously known quasi-para-Sasakian structure in that it is not a normal structure. Instead, it possesses a weaker property called almost normality, similar in properties to integrable tensor structures. Several examples are given, including an almost quasi-para-Sasakian structure defined on the distribution of zero curvature of a sub-Riemanni-an manifold of contact type.

An extended connection with skew-symmetric torsion is defined on an almost quasi-para-Sasakian manifold, which is unique and defined using an intrinsic connection and an endomorphism that preserves the distribution of an almost (para-)contact manifold. The paper proves that the extended connection is a metric connection, and it is also demonstrated that an almost quasi-para-Sasakian manifold can be an η-Einstein manifold with respect to an extended connection with skew-symmetric torsion, provided certain conditions are met.

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Author Biographies

S.V. Galaev, Saratov State University (Saratov, Russiа)

кандидат физико-математических наук, доцент, заведующий кафедрой геометрии механико-математического факультета

E.A. Kokin, Saratov State University (Saratov, Russiа)

аспирант, доцент кафедры геометрии механико-математического факультета

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Published
2023-03-28
How to Cite
Galaev S., Kokin E. On the Geometry of Almost Quasi-Para-Sasakian Manifolds Equipped with a Canonical N-Connection // Izvestiya of Altai State University, 2023, № 1(129). P. 83-88 DOI: 10.14258/izvasu(2023)1-13. URL: http://izvestiya.asu.ru/article/view/%282023%291-13.