Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Comment on Gravity and the Poincare Group   Following the approach of Grignani and Nardelli [1], we show how to cast the
two-dimensional model $L \sim curv^2 + torsion^2 + cosm.const$ -- and in fact
any theory of gravity -- into the form of a Poincare gauge theory. By means of
the above example we then clarify the limitations of this approach: The
diffeomorphism invariance of the action still leads to a nasty constraint
algebra. Moreover, by simple changes of variables (e.g. in a path integral) one
can reabsorb all the modifications of the original theory.

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The categories of this paper are: q-alg
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The categories of this paper are: q-fin
3
The categories of this paper are: physics
4
The categories of this paper are: cond-mat
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The categories of this paper are: alg-geom
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The categories of this paper are: math-ph
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The categories of this paper are: eess
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The categories of this paper are: chem-ph
1
The categories of this paper are: cs
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The categories of this paper are: hep-ex
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The categories of this paper are: solv-int
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The categories of this paper are: plasm-ph
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The categories of this paper are: comp-gas
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The categories of this paper are: nlin
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The categories of this paper are: gr-qc
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The categories of this paper are: funct-an