Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Self-similar cosmological solutions in f(R,T) gravity theory   We study the $f(R,T)$ cosmological models under the self-similarity
hypothesis. We determine the exact form that each physical and geometrical
quantity may take in order that the Field Equations (FE) admit exact
self-similar solutions through the matter collineation approach. We study two
models: the case$\ f(R,T)=f_{1}(R)+f_{2}(T)$ and the case
$f(R,T)=f_{1}(R)+f_{2} (R)f_{3}(T)$. In each case, we state general theorems
which determine completely the form of the unknown functions $f_{i}$ such that
the field equations admit self-similar solutions. We also state some
corollaries as limiting cases. These results are quite general and valid for
any homogeneous self-similar metric$.$ In this way, we are able to generate new
cosmological scenarios. As examples, we study two cases by finding exact
solutions to these particular models.

5
The categories of this paper are: gr-qc
11
The categories of this paper are: hep-lat
31
The categories of this paper are: ao-sci
13
The categories of this paper are: quant-ph
37
The categories of this paper are: supr-con
16
The categories of this paper are: stat
3
The categories of this paper are: physics
4
The categories of this paper are: cond-mat
12
The categories of this paper are: nucl-th
20
The categories of this paper are: acc-phys
28
The categories of this paper are: alg-geom
27
The categories of this paper are: comp-gas
26
The categories of this paper are: bayes-an
30
The categories of this paper are: q-alg
25
The categories of this paper are: patt-sol
36
The categories of this paper are: cmp-lg