NON-RIEMANNIAN COSMIC WALLS AS BOUNDARIES OF SPINNING MATTER WITH TORSION

Abstract

An example of a plane topological defect solution of linearized Einstein–Cartan (EC) field equation representing a cosmic wall boundary of spinning matter is given. The source of Cartan torsion is composed of two orthogonal lines of static polarized spins bounded by the cosmic plane wall. The Kopczyński–Obukhov–Tresguerres (KOT) spin fluid stress–energy current coincides with thin planar matter current in the static case. Our solution is similar to the Letelier solution of Einstein equation for multiple cosmic strings. Due to this fact we suggest that the lines of spinning matter could be analogous to multiple cosmic spinning string solution in EC theory of gravity. When torsion is turned off, a pure Riemannian cosmic wall is obtained.