Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The Magnetospheric Eternally Collapsing Object (MECO) Model of Galactic
  Black Hole Candidates and Active Galactic Nuclei   The spectral, timing, and jet formation properties of neutron stars in low
mass x-ray binary systems are influenced by the presence of central magnetic
moments. Similar features shown by the galactic black hole candidates (GBHC)
strongly suggest that their compact cores might be intrinsically magnetic as
well. We show that the existence of intrinsically magnetic GBHC is consistent
with a new class of solutions of the Einstein field equations of General
Relativity. These solutions are based on a strict adherence to the Strong
Principle of Equivalence (SPOE) requirement that the world lines of physical
matter must remain timelike in all regions of spacetime. The new solutions
emerge when the structure and radiation transfer properties of the energy
momentum tensor on the right hand side of the Einstein field equations are
appropriately chosen to dynamically enforce this SPOE requirement of timelike
world line completeness. In this context, we find that the Einstein field
equations allow the existence of highly red shifted, Magnetospheric, Eternally
Collapsing Objects (MECO). MECO necessarily possess intrinsic magnetic moments
and they do not have trapped surfaces that lead to event horizons and curvature
singularities. Their most striking features are equipartition magnetic fields,
pair plasma atmospheres and extreme gravitational redshifts. Since MECO
lifetimes are orders of magnitude greater than a Hubble time, they provide an
elegant and unified framework for understanding a broad range of observations
of GBHC and active galactic nuclei. We examine their spectral, timing and jet
formation properties and discuss characteristics that might lead to their
confirmation.

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The categories of this paper are: math
35
The categories of this paper are: mtrl-th
11
The categories of this paper are: hep-lat
31
The categories of this paper are: ao-sci
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The categories of this paper are: comp-gas
26
The categories of this paper are: bayes-an
30
The categories of this paper are: q-alg
10
The categories of this paper are: q-bio
23
The categories of this paper are: solv-int
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The categories of this paper are: nucl-th
29
The categories of this paper are: funct-an
5
The categories of this paper are: gr-qc
34
The categories of this paper are: chem-ph
20
The categories of this paper are: acc-phys
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The categories of this paper are: hep-th
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The categories of this paper are: cond-mat