Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A note on a straight gravity tunnel through a rotating body   It is well-known that the straight gravity tunnel between any two different
positions on a non-rotating Earth, which has uniform density, is traversable,
i.e., an object initially at rest will reach its destination through the
gravity tunnel in both directions. Moreover, the time taken to fall is always
constant. These facts are no longer true if rotation is allowed. The aim of
this note is to derive the necessary and sufficient condition for
traversability of straight gravity tunnels through a rotating physical body
with spherically symmetric gravitational field. Fall-through times are
expressed in a closed form for linear and constant gravitational fields. In
conclusion, these models are compared to numerically obtained data using the
internal structure of the Earth.

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The categories of this paper are: cond-mat
17
The categories of this paper are: q-fin
19
The categories of this paper are: eess
36
The categories of this paper are: cmp-lg
10
The categories of this paper are: q-bio
37
The categories of this paper are: supr-con
22
The categories of this paper are: chao-dyn
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The categories of this paper are: astro-ph
34
The categories of this paper are: chem-ph
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The categories of this paper are: math-ph
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The categories of this paper are: stat
35
The categories of this paper are: mtrl-th
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The categories of this paper are: nlin
30
The categories of this paper are: q-alg
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The categories of this paper are: gr-qc
28
The categories of this paper are: alg-geom