Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Measurements of Black Hole Spins and Tests of Strong-Field General
  Relativity   Fast variability studies of accreting black holes in the Galaxy offer us a
unique opportunity to measure the spins of black holes and test the
strong-field behavior of general relativity. In this review, I summarize the
arguments often used in attempts of measuring the spins of black holes,
concentrating on their theoretical foundations. I also argue that X-ray studies
of accreting black holes will be able to provide in the future strong
constraints on deviations from general relativity in the strong-field regime.

22
The categories of this paper are: chao-dyn
26
The categories of this paper are: bayes-an
19
The categories of this paper are: eess
27
The categories of this paper are: comp-gas
12
The categories of this paper are: nucl-th
24
The categories of this paper are: dg-ga
10
The categories of this paper are: q-bio
7
The categories of this paper are: hep-th
28
The categories of this paper are: alg-geom
23
The categories of this paper are: solv-int
33
The categories of this paper are: plasm-ph
5
The categories of this paper are: gr-qc
31
The categories of this paper are: ao-sci
11
The categories of this paper are: hep-lat
15
The categories of this paper are: nucl-ex
36
The categories of this paper are: cmp-lg