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Relativistic Disks as Sources of Kerr-Newman Fields

T. Ledvinka·M. Zofka·J. Bicak
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Abstract

If an appropriate region of Kerr-Newman space-time is removed and suitable identifications are made, the resulting space-time can be interpreted as an infinitely thin disk producing the original electromagnetic and gravitational fields. We choose the shape of the regions removed in such a way that radial pressures in the disks vanish. Even the very inner parts such as ergoregions may exist around the disks. The surface energy-momentum tensor of the disks is checked to satisfy the weak and strong energy conditions. To emphasize the reality of these sources two models of the disks are presented: (i) rotating conductive charged rings which are supported against collapse by their internal pressure, (ii) two counter-rotating streams of charged particles moving along circular electro-geodesics. All these disk sources form a three-dimensional parameter space with specific electric charge Q/M, angular momentum a/M and the size of the excluded region being the parameters.

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T. Ledvinka, M. Zofka, J. Bicak. 1998-01-15. Relativistic Disks as Sources of Kerr-Newman Fields. https://arxiv.org/abs/gr-qc/9801053

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