Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Models of Collapsing and Expanding Anisotropic Gravitating Source in
  $f(R,T)$ Theory of Gravity   In this paper, we have formulated the exact solutions of the non-static
anisotropic gravitating source in $f(R,T)$ gravity which may lead to expansion
and collapse. By assuming the no thermal conduction in gravitating source, we
have determine parametric solutions in $f(R,T)$ gravity with non-static
spherical geometry filled with anisotropic fluid. We have examined the range of
parameter for which expansion scalar become negative and positive leading to
collapse and expansion, respectively. Further, using the definition of mass
function the condition for the trapped surface have been explored and it has
been investigated there exists a single horizon in this case. The impact of
coupling parameter $\lambda$ has been discussed in detail in both cases. For
the various values of coupling parameter $\lambda$, we have plotted energy
density, anisotropic pressure and anisotropic parameter in case of collapse and
expansion. The physical significance of the graphs has been explained in
detail.

1
The categories of this paper are: cs
22
The categories of this paper are: chao-dyn
32
The categories of this paper are: atom-ph
27
The categories of this paper are: comp-gas
34
The categories of this paper are: chem-ph
6
The categories of this paper are: astro-ph
16
The categories of this paper are: stat
3
The categories of this paper are: physics
17
The categories of this paper are: q-fin
11
The categories of this paper are: hep-lat
0
The categories of this paper are: hep-ph
19
The categories of this paper are: eess
26
The categories of this paper are: bayes-an
33
The categories of this paper are: plasm-ph
24
The categories of this paper are: dg-ga
14
The categories of this paper are: math-ph