Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Nonminimal coupling, equivalence principle and exact Foldy-Wouthuysen
  transformation   It is shown that the exact Foldy-Wouthuysen transformation for spin-0
particles on spacetimes described by the metrics $ds^2 = V^2 dt^2 - W^2 d
{\bf{x}}^2$, where $V=V({\bf{x}})$ and $W=W({\bf{x}})$, only exists if the
scalar field is nonminimally coupled to the Ricci scalar field with a coupling
constant equal to 1/6. The nonminimal coupling term, in turn, does not violate
the equivalence principle. As an application we obtain the nonrelativistic
Foldy-Wouthuysen Hamiltonian concerning the general solution to the linearized
field equations of higher-derivative gravity for a static pointlike source in
the Teyssandier gauge.

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The categories of this paper are: solv-int
18
The categories of this paper are: econ
12
The categories of this paper are: nucl-th
29
The categories of this paper are: funct-an
0
The categories of this paper are: hep-ph
16
The categories of this paper are: stat
30
The categories of this paper are: q-alg
33
The categories of this paper are: plasm-ph
32
The categories of this paper are: atom-ph
15
The categories of this paper are: nucl-ex
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The categories of this paper are: bayes-an
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The categories of this paper are: astro-ph
11
The categories of this paper are: hep-lat
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The categories of this paper are: dg-ga
28
The categories of this paper are: alg-geom
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The categories of this paper are: eess