46 citations · 269 across the 40 of their papers we have counts for
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Tensor Operations on Degenerate Inner Product Spaces
Ovidiu Cristinel Stoica
Well-known operations defined on a non-degenerate inner product vector space are extended to the case of a degenerate inner product. The main obstructions to the extension of these…
Kerr-Newman Solutions with Analytic Singularity and no Closed Timelike Curves
Ovidiu-Cristinel Stoica
It is shown that the Kerr-Newman solution, representing charged and rotating stationary black holes, admits analytic extension at the singularity. This extension is obtained by usi…
Cartan's Structural Equations for Singular Manifolds
Ovidiu Cristinel Stoica
The classical Cartan's structural equations show in a compact way the relation between a connection and its curvature, and reveals their geometric interpretation in terms of moving…
Spacetimes with Singularities
Ovidiu Cristinel Stoica
We report on some advances made in the problem of singularities in general relativity. First is introduced the singular semi-Riemannian geometry for metrics which can change their…
The Geometry of Warped Product Singularities
Ovidiu Cristinel Stoica
In this article the degenerate warped products of singular semi-Riemannian manifolds are studied. They were used recently by the author to handle singularities occurring in General…
On Singular Semi-Riemannian Manifolds
Ovidiu Cristinel Stoica
On a Riemannian or a semi-Riemannian manifold, the metric determines invariants like the Levi-Civita connection and the Riemann curvature. If the metric becomes degenerate (as in s…