Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Higgs Mechanism and the Structure of the Energy-Momentum Tensor in
  Einstein Gravity and Conformal Gravity   In the standard treatment of the Einstein gravitational theory the
energy-momentum tensor has always been taken to be composed of perfect fluid
aggregates of kinematic Newtonian point test particles with fundamental
mechanical masses. Moreover, this standard prescription was not revised after
the discovery of the mass-generating Higgs mechanism which is known to be
present in the elementary particle physics of these self-same sources and which
is also required in the conformal invariant gravitational alternative being
considered by Mannheim and Kazanas. In this short contribution we show that
despite the presence of the Higgs mechanism, the standard geodesic motion and
Euler hydrodynamics still obtain in the one-particle sector of the theory even
while the overall energy-momentum tensor differs substantially from the
conventional kinematic one.

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The categories of this paper are: bayes-an
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The categories of this paper are: math
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The categories of this paper are: alg-geom
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The categories of this paper are: cmp-lg
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The categories of this paper are: q-fin
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The categories of this paper are: econ
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The categories of this paper are: patt-sol
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The categories of this paper are: chao-dyn
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The categories of this paper are: astro-ph
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The categories of this paper are: nucl-th
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The categories of this paper are: supr-con
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The categories of this paper are: adap-org
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The categories of this paper are: hep-ex
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The categories of this paper are: math-ph
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The categories of this paper are: solv-int
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The categories of this paper are: nlin