Charged perfect fluid disks as sources of Taub-NUT-type spacetimes

TL;DR

This paper presents a method to interpret Taub-NUT-type spacetimes as finite charged perfect fluid disks, showing electromagnetic fields significantly alter the disks' material properties and satisfy energy conditions.

Contribution

It introduces an inverse problem approach to model charged perfect fluid disks as sources of Taub-NUT-type solutions, highlighting electromagnetic effects on disk properties.

Findings

Electromagnetic fields change the material properties of the disks.

Finite charged perfect fluid disks can satisfy all energy conditions.

The approach simplifies the diagonalization of the energy-momentum tensor.

Abstract

The interpretation of a family of electrovacuum stationary Taub-NUT-type fields in terms of finite charged perfect fluid disks is presented. The interpretation is mades by means of an "inverse problem" approach used to obtain disk sources of known solutions of the Einstein or Einstein-Maxwell equations. The diagonalization of the energy-momentum tensor of the disks is facilitated in this case by the fact that it can be written as an upper right triangular matrix. We find that the inclusion of electromagnetic fields changes significatively the different material properties of the disks and so we can obtain, for some values of the parameters, finite charged perfect fluid disks that are in agreement with all the energy conditions.