arXiv subjects

Salah Gomaa Elgendi

Publications and source records attributed to Salah Gomaa Elgendi.

2 recordsLinked to original sources

arXiv2024

Metrizability of SO(3)-invariant connections: Riemann versus Finsler

For a torsion-free affine connection on a given manifold, which does not necessarily arise as the Levi-Civita connection of any pseudo-Riemannian metric, it is still possible that it corresponds in a canonical way to a Finsler structure; this property is known as Finsler (or Berwald-Finsler) metrizability. In the present paper, we clarify, for 4-dimensional SO(3)-invariant, Berwald-Finsler metrizable connections, the issue of the existence of an affinely equivalent pseudo-Riemannian structure. In particular, we find all classes of SO(3)-invariant connections which are not Levi-Civita connections for any pseudo-Riemannian metric - hence, are non-metric in a conventional way - but can still be metrized by SO(3)-invariant Finsler functions. The implications for physics, together with some examples are briefly discussed.

math.DG↗

arXiv2023

On the Existence of Parallel one Forms

In this paper, using the Finslerian settings, we study the existence of parallel one forms (or, equivalently parallel vector fields) on a Riemannian manifold. We show that a parallel one form on a Riemannian manifold M is a holonomy invariant function on the tangent bundle T M with respect to the geodesic spray. We prove that if the metrizability freedom of the geodesic spray of (M, F) is 1, then the (M, F) does not admit a parallel one form. We investigate a sufficient condition on a Riemannian manifold to admit a parallel one form. As a by-product, we relate the existence of a proper affine Killing vector field by the metrizability freedom. We establish sufficient conditions for the existence of a parallel one form on a Finsler manifold. By counter-examples, we show that if the metrizability freedom is greater than 1, then the manifold (Riemannian or Finslerian) does not necessarily admit a parallel one form. Various special cases and examples are studied and discussed.

math.DG↗