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arXiv · 1012.1400

On the Static Spacetime of a Single Point Charge

A. Shadi Tahvildar-Zadeh
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Abstract

Among all electromagnetic theories which (a) are derivable from a Lagrangian, (b) satisfy the dominant energy condition, and (c) in the weak field limit coincide with classical linear electromagnetics, we identify a certain subclass with the property that the corresponding static, spherically symmetric, asymptotically flat electrovacuum spacetime metric has the mildest possible singularity at its center, namely, a conical singularity on the time axis. The electric field moreover has a point defect on the time axis, its total energy is finite, and is equal to the ADM mass of the spacetime. By an appropriate scaling of the Lagrangian, one can arrange the total mass and total charge of these spacetimes to have any chosen values. For small enough mass-to-charge ratio, these spacetimes have no horizons and no trapped null geodesics. We prove the uniqueness of these solutions in the spherically symmetric class. We conclude by performing a qualitative study of the geodesics and test-charge trajectories of these spacetimes.

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A. Shadi Tahvildar-Zadeh. 2010-12-07. On the Static Spacetime of a Single Point Charge. https://doi.org/10.1142/s0129055x11004308

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