Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Finite-time future singularities in modified Gauss-Bonnet and
  $\mathcal{F}(R,G)$ gravity and singularity avoidance   We study all four types of finite-time future singularities emerging in
late-time accelerating (effective quintessence/phantom) era from
$\mathcal{F}(R,G)$-gravity, where $R$ and $G$ are the Ricci scalar and the
Gauss-Bonnet invariant, respectively. As an explicit example of
$\mathcal{F}(R,G)$-gravity, we also investigate modified Gauss-Bonnet gravity,
so-called $F(G)$-gravity. In particular, we reconstruct the $F(G)$-gravity and
$\mathcal{F}(R,G)$-gravity models where accelerating cosmologies realizing the
finite-time future singularities emerge. Furthermore, we discuss a possible way
to cure the finite-time future singularities in $F(G)$-gravity and
$\mathcal{F}(R,G)$-gravity by taking into account higher-order curvature
corrections. The example of non-singular realistic modified Gauss-Bonnet
gravity is presented. It turns out that adding such non-singular modified
gravity to singular Dark Energy makes the combined theory to be non-singular
one as well.

11
The categories of this paper are: hep-lat
12
The categories of this paper are: nucl-th
25
The categories of this paper are: patt-sol
21
The categories of this paper are: adap-org
2
The categories of this paper are: math
3
The categories of this paper are: physics
10
The categories of this paper are: q-bio
13
The categories of this paper are: quant-ph
26
The categories of this paper are: bayes-an
15
The categories of this paper are: nucl-ex
30
The categories of this paper are: q-alg
20
The categories of this paper are: acc-phys
18
The categories of this paper are: econ
28
The categories of this paper are: alg-geom
24
The categories of this paper are: dg-ga
8
The categories of this paper are: hep-ex