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On almost cosymplectic generalized (k, μ)ʹ-spaces

  • Fortuné Massamba EMAIL logo
Veröffentlicht/Copyright: 9. August 2025
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Abstract

We introduce and study almost cosymplectic manifolds whose characteristic vector field ξ belongs to a generalized (k, μ)ʹ-nullity distribution, which involves the tensor = φ ◦ h. If ≠ 0, we prove that the smooth functions k and μ are uniquely determined by k < 0 and μ = ξ(ln λ), where λ=k. Moreover, we show that the spectrum of is {0, λ,−λ} and that the considered manifolds cannot be Ricci symmetric. Under certain conditions, we further prove that such manifolds are locally a warped product. Examples are also provided.


The author would like to thank the Institut des Hautes Études Scientifiques (IHES), Bures-Sur-Yvette (France) for its hospitality and support during the preparation of this paper. This work is partially supported by the National Research Foundation of South Africa.


  1. (Communicated by Tibor Macko)

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Received: 2024-09-24
Accepted: 2025-04-01
Published Online: 2025-08-09
Published in Print: 2025-08-26

© 2025 Mathematical Institute Slovak Academy of Sciences

Heruntergeladen am 15.12.2025 von https://www.degruyterbrill.com/document/doi/10.1515/ms-2025-0067/pdf
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