Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Topological field theories in n-dimensional spacetimes and Cartan's
  equations   Action principles of the BF type for diffeomorphism invariant topological
field theories living in n-dimensional spacetime manifolds are presented. Their
construction is inspired by Cuesta and Montesinos' recent paper where Cartan's
first and second structure equations together with first and second Bianchi
identities are treated as the equations of motion for a field theory. In
opposition to that paper, the current approach involves also auxiliary fields
and holds for arbitrary n-dimensional spacetimes. Dirac's canonical analysis
for the actions is detailedly carried out in the generic case and it is shown
that these action principles define topological field theories, as mentioned.
The current formalism is a generic framework to construct geometric theories
with local degrees of freedom by introducing additional constraints on the
various fields involved that destroy the topological character of the original
theory. The latter idea is implemented in two-dimensional spacetimes where
gravity coupled to matter fields is constructed out, which has indeed local
excitations.

29
The categories of this paper are: funct-an
22
The categories of this paper are: chao-dyn
8
The categories of this paper are: hep-ex
14
The categories of this paper are: math-ph
20
The categories of this paper are: acc-phys
4
The categories of this paper are: cond-mat
31
The categories of this paper are: ao-sci
17
The categories of this paper are: q-fin
33
The categories of this paper are: plasm-ph
27
The categories of this paper are: comp-gas
3
The categories of this paper are: physics
15
The categories of this paper are: nucl-ex
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The categories of this paper are: solv-int
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The categories of this paper are: hep-lat
24
The categories of this paper are: dg-ga
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The categories of this paper are: chem-ph