Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The Schwarzschild solution in a Kaluza-Klein theory with two times   A new spherically-symmetric solution is determined in a noncompactified
Kaluza-Klein theory in which a time character is ascribed to the fifth
coordinate. This solution contains two independent parameters which are related
with mass and electric charge. The solution exhibits a Schwarzschild radius and
represents a generalization of the Schwarzschild solution in four dimensions.
The parameter of the solution connected with the electric charge depends on the
derivative of the fifth (second time) coordinate with respect to the ordinary
time coordinate. It is shown that the perihelic motion in four-dimensional
relativity has a counterpart in five dimensions in the perinucleic motion of a
negatively-charged particle. If the quantization conditions of the older
quantum theory are applied to that motion, an analogue of the fine-structure
formula of atomic spectra is obtained.

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The categories of this paper are: dg-ga
11
The categories of this paper are: hep-lat
12
The categories of this paper are: nucl-th
20
The categories of this paper are: acc-phys
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The categories of this paper are: comp-gas
28
The categories of this paper are: alg-geom
33
The categories of this paper are: plasm-ph
18
The categories of this paper are: econ
32
The categories of this paper are: atom-ph
9
The categories of this paper are: nlin
26
The categories of this paper are: bayes-an
8
The categories of this paper are: hep-ex
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The categories of this paper are: q-fin
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The categories of this paper are: nucl-ex
21
The categories of this paper are: adap-org
30
The categories of this paper are: q-alg