Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Numerical evolution of shocks in the interior of Kerr black holes   We numerically solve Einstein's equations coupled to a scalar field in the
interior of Kerr black holes. We find shock waves form near the inner horizon.
The shocks grow exponentially in amplitude and need not be axisymmetric.
Observers who pass through the shocks experience exponentially large tidal
forces and are accelerated exponentially close to the speed of light.

4
The categories of this paper are: cond-mat
3
The categories of this paper are: physics
26
The categories of this paper are: bayes-an
18
The categories of this paper are: econ
14
The categories of this paper are: math-ph
13
The categories of this paper are: quant-ph
25
The categories of this paper are: patt-sol
22
The categories of this paper are: chao-dyn
34
The categories of this paper are: chem-ph
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The categories of this paper are: acc-phys
21
The categories of this paper are: adap-org
33
The categories of this paper are: plasm-ph
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The categories of this paper are: comp-gas
15
The categories of this paper are: nucl-ex
2
The categories of this paper are: math
28
The categories of this paper are: alg-geom