Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A relativistic algorithm with isotropic coordinates   We study spherically symmetric spacetimes for matter distributions with
isotropic pressures. We generate new exact solutions to the Einstein field
equations which also contains isotropic pressures. We develop an algorithm that
produces a new solution if a particular solution is known. The algorithm leads
to a nonlinear Bernoulli equation which can be integrated in terms of arbitrary
functions. We use a conformally flat metric to show that the integrals may be
expressed in terms of elementary functions. It is important to note that we
utilise isotropic coordinates unlike other treatments.

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The categories of this paper are: nlin
33
The categories of this paper are: plasm-ph
22
The categories of this paper are: chao-dyn
27
The categories of this paper are: comp-gas
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The categories of this paper are: bayes-an
14
The categories of this paper are: math-ph
12
The categories of this paper are: nucl-th
36
The categories of this paper are: cmp-lg
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The categories of this paper are: q-bio
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The categories of this paper are: eess
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The categories of this paper are: econ
29
The categories of this paper are: funct-an
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The categories of this paper are: dg-ga
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The categories of this paper are: solv-int
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The categories of this paper are: hep-lat
30
The categories of this paper are: q-alg