Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Involutive Spacetime Distributions and p-Brane Dynamics   We propose a precise definition of multidimensional fluids generated by
self-gravitating extended objects such as strings and membranes: a
p-dimensional perfect fluid is a smooth involutive p-dimensional distribution
on a spacetime, each integral manifold of which is a timelike, connected,
immersed submanifold of dimension, p -- representing the history of a
(p-1)-dimensional extended object. This geometric formulation of perfect fluids
of higher dimensions naturally leads to the associated stress-energy tensor.
Furthermore, the laws of temporal evolution and symmetries of such systems are
derived, in general, from the Einstein field equations and the integrability
conditions. We also present a matter model based on a 2-dimensional involutive
distribution, and it is shown that the stress-energy tensor for
self-gravitating strings gives rise to a non-trivial spherically symmetric
spacetime with a naked singularity.

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The categories of this paper are: bayes-an
20
The categories of this paper are: acc-phys
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The categories of this paper are: alg-geom
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The categories of this paper are: econ
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The categories of this paper are: adap-org
35
The categories of this paper are: mtrl-th
9
The categories of this paper are: nlin
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The categories of this paper are: solv-int
11
The categories of this paper are: hep-lat
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The categories of this paper are: nucl-th
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The categories of this paper are: patt-sol
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The categories of this paper are: chem-ph
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The categories of this paper are: chao-dyn
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The categories of this paper are: plasm-ph
5
The categories of this paper are: gr-qc
10
The categories of this paper are: q-bio