Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Killing tensor and Carter constant for Painleve-Gullstrand form of
  Lense-Thirring spacetime   Recently, the authors have formulated and explored a novel
Painleve-Gullstrand variant of the Lense-Thirring spacetime, which has some
particularly elegant features -- including unit-lapse, intrinsically flat
spatial 3-slices, and some particularly simple geodesics, the "rain" geodesics.
At linear level in the rotation parameter this spacetime is indistinguishable
from the usual slow-rotation expansion of Kerr. Herein, we shall show that this
spacetime possesses a nontrivial Killing tensor, implying separability of the
Hamilton-Jacobi equation. Furthermore, we shall show that the Klein-Gordon
equation is also separable on this spacetime. However, while the Killing tensor
has a 2-form square root, we shall see that this 2-form square root of the
Killing tensor is not a Killing-Yano tensor. Finally, the
Killing-tensor-induced Carter constant is easily extracted, and now, with a
fourth constant of motion, the geodesics become (in principle) explicitly
integrable.

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The categories of this paper are: ao-sci
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The categories of this paper are: q-bio
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The categories of this paper are: q-alg
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The categories of this paper are: q-fin
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The categories of this paper are: mtrl-th
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The categories of this paper are: astro-ph
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The categories of this paper are: nucl-th
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The categories of this paper are: quant-ph
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The categories of this paper are: acc-phys
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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: cs
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The categories of this paper are: nucl-ex
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The categories of this paper are: physics
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The categories of this paper are: atom-ph
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The categories of this paper are: eess