Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Geometric sigma model of the Universe   The purpose of this work is to demonstrate how an arbitrarily chosen
background of the Universe can be made a solution of a simple geometric sigma
model. Geometric sigma models are purely geometric theories in which spacetime
coordinates are seen as scalar fields coupled to gravity. Although they look
like ordinary sigma models, they have the peculiarity that their complete
matter content can be gauged away. The remaining geometric theory possesses a
background solution that is predefined in the process of constructing the
theory. The fact that background configuration is specified in advance is
another peculiarity of geometric sigma models. In this paper, I construct
geometric sigma models based on different background geometries of the
Universe. Whatever background geometry is chosen, the dynamics of its small
perturbations is shown to posses a generic classical stability. This way, any
freely chosen background metric is made a stable solution of a simple model.
Three particular models of the Universe are considered as examples of how this
is done in practice.

28
The categories of this paper are: alg-geom
4
The categories of this paper are: cond-mat
25
The categories of this paper are: patt-sol
26
The categories of this paper are: bayes-an
32
The categories of this paper are: atom-ph
17
The categories of this paper are: q-fin
0
The categories of this paper are: hep-ph
14
The categories of this paper are: math-ph
20
The categories of this paper are: acc-phys
19
The categories of this paper are: eess
13
The categories of this paper are: quant-ph
3
The categories of this paper are: physics
35
The categories of this paper are: mtrl-th
30
The categories of this paper are: q-alg
11
The categories of this paper are: hep-lat
36
The categories of this paper are: cmp-lg