Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: An electromagnetic extension of the Schwarzschild interior solution and
  the corresponding Buchdahl limit   We wish to construct a model for charged star as a generalization of the
uniform density Schwarzschild interior solution. We employ the Vaidya and
Tikekar ansatz [{\it Astrophys. Astron.} {\bf 3} (1982) 325] for one of the
metric potentials and electric field is chosen in such a way that when it is
switched off the metric reduces to the Schwarzschild. This relates charge
distribution to the Vaidya-Tikekar parameter, $k$, indicating deviation form
sphericity of three dimensional space when embedded into four dimensional
Euclidean space. The model is examined against all the physical conditions
required for a relativistic charged fluid sphere as an interior to a charged
star. We also obtain and discuss charged analogue of the Buchdahl compactness
bound.

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The categories of this paper are: eess
36
The categories of this paper are: cmp-lg
7
The categories of this paper are: hep-th
32
The categories of this paper are: atom-ph
1
The categories of this paper are: cs
29
The categories of this paper are: funct-an
22
The categories of this paper are: chao-dyn
30
The categories of this paper are: q-alg
12
The categories of this paper are: nucl-th
13
The categories of this paper are: quant-ph
34
The categories of this paper are: chem-ph
27
The categories of this paper are: comp-gas
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The categories of this paper are: math-ph
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The categories of this paper are: econ
6
The categories of this paper are: astro-ph
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The categories of this paper are: solv-int