Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The Evolution of Viscous Inclined Disks in Axisymmetric and Triaxial
  Galaxies   We have used a set of equations developed by Pringle (1992) to follow the
evolution of a viscous twisted disk in a galaxy-like potential which is
stationary or tumbling relative to inertial space. In an axisymmetric
potential, the disk settles to the equatorial plane at a rate determined
largely by the coefficient $\nu_2$ associated with shear perpendicular to the
local disk plane. If the disk is initially close to the galaxy equator, the
rate at which the inclination decays is well described by the analytic formula
of Steiman-Cameron and Durisen (1988); in a highly inclined disk, `breaking
waves' of curvature steepen as they propagate through the disk, rendering the
numerical treatment untrustworthy. In a triaxial potential which is stationary
in inertial space, settling is faster than in an oblate or prolate galaxy,
since the disk twists simultaneously about two perpendicular axes. If the
figure of the potential tumbles about one of its principal axes, the viscous
disk can settle into a warped state in which gas at each radius follows a
stable tilted orbit which precesses so as to remain stationary relative to the
underlying galaxy.

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The categories of this paper are: cond-mat
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The categories of this paper are: chem-ph
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The categories of this paper are: cmp-lg
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The categories of this paper are: chao-dyn
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The categories of this paper are: acc-phys
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The categories of this paper are: quant-ph
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The categories of this paper are: atom-ph
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The categories of this paper are: nucl-th
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The categories of this paper are: q-bio
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The categories of this paper are: q-fin
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The categories of this paper are: physics
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The categories of this paper are: adap-org
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The categories of this paper are: math-ph
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The categories of this paper are: supr-con
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The categories of this paper are: funct-an
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The categories of this paper are: cs