Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Does gravitational collapse lead to singularities?   According to conventional modelling by general relativity the collapse of
radially symmetric gravitating objects may end in a singular state. But by
inclusion of potential energy into the energy tensor, which is required to
guarantee global energy conservation, the occurrence of singularities is
avoided. Instead the final states of the collapse of mass concentrations of
arbitrary size are nuclear matter objects, from which jets of matter can be
recycled into space. The mysterious dark energy, supposed as the main
constituent of the universe, may even be the potential energy of matter itself.

27
The categories of this paper are: comp-gas
25
The categories of this paper are: patt-sol
13
The categories of this paper are: quant-ph
11
The categories of this paper are: hep-lat
10
The categories of this paper are: q-bio
12
The categories of this paper are: nucl-th
34
The categories of this paper are: chem-ph
1
The categories of this paper are: cs
14
The categories of this paper are: math-ph
29
The categories of this paper are: funct-an
35
The categories of this paper are: mtrl-th
23
The categories of this paper are: solv-int
20
The categories of this paper are: acc-phys
37
The categories of this paper are: supr-con
15
The categories of this paper are: nucl-ex
19
The categories of this paper are: eess