Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: On a zero-gravity limit of the Kerr--Newman spacetimes and their
  electromagnetic fields   We discuss the limit of vanishing $G$ (Newton's constant of universal
gravitation) of the maximal analytically extended Kerr--Newman electrovacuum
spacetimes {represented in Boyer--Lindquist coordinates}. We investigate the
topologically nontrivial spacetime emerging in this limit and show that it
consists of two copies of flat Minkowski spacetime glued at a timelike solid
cylinder. As $G\to 0$, the electromagnetic fields of the Kerr-Newman spacetimes
converge to nontrivial solutions of Maxwell's equations on this background
spacetime. We show how to obtain these fields by solving Maxwell's equations
with singular sources supported only on a circle in a spacelike slice of the
spacetime. These sources do not suffer from any of the pathologies that plague
the alternate sources found in previous attempts to interpret the Kerr--Newman
fields on the topologically simple Minkowski spacetime. We characterize the
singular behavior of these sources and prove that the Kerr-Newman electrostatic
potential and magnetic stream function are the unique solutions of the Maxwell
equations among all functions that have the same blow-up behavior at the ring
singularity.

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The categories of this paper are: hep-ex
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The categories of this paper are: chao-dyn
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The categories of this paper are: patt-sol
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The categories of this paper are: alg-geom
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The categories of this paper are: hep-th
17
The categories of this paper are: q-fin
34
The categories of this paper are: chem-ph
30
The categories of this paper are: q-alg
3
The categories of this paper are: physics
16
The categories of this paper are: stat
31
The categories of this paper are: ao-sci
1
The categories of this paper are: cs
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The categories of this paper are: mtrl-th
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The categories of this paper are: cond-mat
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The categories of this paper are: dg-ga
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The categories of this paper are: hep-lat