Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: El experimento de Cavendish   In this article, we present a description of the \textit{apparatus} employed
by Henry Cavendish, which in turn is actually a compendium of 17 complex
experiments, to try to experimentally measure the universal gravitation
constant, theoretically posed by the divine Sir Isaac Newton, in his monumental
\textit{Principia Mathematica}.\\ Since the gravitational force is very small,
gravitational experiments in the laboratory are highly susceptible to strange
disturbances. Measuring gravitation in the laboratory is then that problematic
and today such difficulties persist.

33
The categories of this paper are: plasm-ph
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The categories of this paper are: chem-ph
21
The categories of this paper are: adap-org
17
The categories of this paper are: q-fin
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The categories of this paper are: supr-con
8
The categories of this paper are: hep-ex
23
The categories of this paper are: solv-int
13
The categories of this paper are: quant-ph
28
The categories of this paper are: alg-geom
6
The categories of this paper are: astro-ph
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The categories of this paper are: nlin
12
The categories of this paper are: nucl-th
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The categories of this paper are: eess
4
The categories of this paper are: cond-mat
11
The categories of this paper are: hep-lat
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The categories of this paper are: funct-an