About the Journal

Editor in Chief - Anry Nersessian (Institute of Mathematics NAS, Armenia)

Deputy Editor - Rafayel Barkhudaryan (Institute of Mathematics NAS, Armenia)

Managing Editor - Linda Khachatryan (Institute of Mathematics NAS, Armenia)
e-mail: ajm@instmath.sci.am 

Announcements

Current Issue Vol. 18 No. 1 (2026): Biharmonic Helices in Three-Dimensional Lorentzian Egorov and $\varepsilon$-Spaces

  • Articles

    Biharmonic Helices in Three-Dimensional Lorentzian Egorov and $\varepsilon$-Spaces

    Fatima Zahra Benzahra-Belkacem, Dr. Noura Sidhoumi
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    Abstract

    We consider three-dimensional Lorentzian Egorov and $\varepsilon$-spaces and show that the existence of proper biharmonic helices in these manifolds is highly constrained and closely tied to the causal character of the Frenet frame. In particular, we prove that no proper biharmonic helices exist in Egorov spaces unless the space is flat and the normal vector is spacelike. Furthermore, we establish that no proper biharmonic helices exist in three-dimensional $\varepsilon$-spaces.

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