Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The Spatial Averaging Limit of Covariant Macroscopic Gravity - Scalar
  Corrections to the Cosmological Equations   It is known that any explicit averaging scheme of the type essential for
describing the large scale behaviour of the Universe, must necessarily yield
corrections to the Einstein equations applied in the Cosmological setting. The
question of whether or not the resulting corrections to the Einstein equations
are significant, is still a subject of debate, partly due to possible
ambiguities in the averaging schemes available. In particular, it has been
argued in the literature that the effects of averaging could be gauge
artifacts. We apply the formalism of Zalaletdinov's Macroscopic Gravity (MG)
which is a fully covariant and nonperturbative averaging scheme, in an attempt
to construct gauge independent corrections to the standard
Friedmann-Lemaitre-Robertson-Walker (FLRW) equations. We find that whereas one
cannot escape the problem of dependence on \emph{one} gauge choice -- which is
inherent in the assumption of large scale homogeneity and isotropy -- it is
however possible to construct \emph{spacetime scalar} corrections to the
standard FLRW equations. This partially addresses the criticism concerning the
corrections being gauge artifacts. For a particular initial choice of gauge
which simplifies the formalism, we explicitly construct these scalars in terms
of the underlying inhomogeneous geometry, and incidentally demonstrate that the
formal structure of the corrections with this gauge choice is identical to that
of analogous corrections derived by Buchert in the context of spatial averaging
of scalars.

2
The categories of this paper are: math
14
The categories of this paper are: math-ph
3
The categories of this paper are: physics
15
The categories of this paper are: nucl-ex
33
The categories of this paper are: plasm-ph
28
The categories of this paper are: alg-geom
4
The categories of this paper are: cond-mat
30
The categories of this paper are: q-alg
35
The categories of this paper are: mtrl-th
11
The categories of this paper are: hep-lat
27
The categories of this paper are: comp-gas
31
The categories of this paper are: ao-sci
24
The categories of this paper are: dg-ga
10
The categories of this paper are: q-bio
36
The categories of this paper are: cmp-lg
23
The categories of this paper are: solv-int