Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Shape of black holes   It is well known that celestial bodies tend to be spherical due to gravity
and that rotation produces deviations from this sphericity. We discuss what is
known and expected about the shape of black holes' horizons from their
formation to their final, stationary state.
  We present some recent results showing that black hole rotation indeed
manifests in the widening of their central regions, limits their global shapes
and enforces their whole geometry to be close to the extreme Kerr horizon
geometry at almost maximal rotation speed. The results depend only on the
horizon area and angular momentum. In particular they are entirely independent
of the surrounding geometry of the spacetime and of the presence of matter
satisfying the strong energy condition. We also discuss the the relation of
this result with the Hoop conjecture.

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The categories of this paper are: cond-mat
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The categories of this paper are: math
1
The categories of this paper are: cs
12
The categories of this paper are: nucl-th
9
The categories of this paper are: nlin
14
The categories of this paper are: math-ph
20
The categories of this paper are: acc-phys
3
The categories of this paper are: physics
36
The categories of this paper are: cmp-lg
31
The categories of this paper are: ao-sci
13
The categories of this paper are: quant-ph
11
The categories of this paper are: hep-lat
26
The categories of this paper are: bayes-an
30
The categories of this paper are: q-alg
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The categories of this paper are: hep-th
19
The categories of this paper are: eess