Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The Momentum Four-Vector in the $e\psi$N Formalism and the Angular
  Momentum Imparted to Test Particles by Gravitational Waves   Since gravitational waves are solutions of Einstein's field equations with a
zero stress-energy tensor, the reality of these waves was questioned. To
demonstrate it, the momentum imparted to test particles by such waves was
evaluated. A closed form expression for this quantity was provided by Qadir and
Sharif, using an extension of the pseudo-Newtonian formalism. That formalism
carried with it the zero component of the momentum vector, which could not be
interpreted as the energy imparted to the test particle. Sharif proposed that
it may represent the angular momentum imparted to test particles by
gravitational waves. In this paper it is shown that this interpretation is not
valid. An alternative explanation has been provided.

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The categories of this paper are: eess
34
The categories of this paper are: chem-ph
37
The categories of this paper are: supr-con
31
The categories of this paper are: ao-sci
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The categories of this paper are: stat
0
The categories of this paper are: hep-ph
1
The categories of this paper are: cs
36
The categories of this paper are: cmp-lg
35
The categories of this paper are: mtrl-th
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The categories of this paper are: acc-phys
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The categories of this paper are: solv-int
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The categories of this paper are: alg-geom
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The categories of this paper are: quant-ph
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The categories of this paper are: hep-th
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The categories of this paper are: hep-lat
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The categories of this paper are: q-bio