Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Dark Energy and the Spinning Superparticle   We revisit the theory of background fields constructed on the BRST-algebra of
a spinning particle with $\mathcal{N}=4$ worldline supersymmetry, whose
spectrum contains the graviton but no other fields. On a generic background,
the closure of the BRST algebra implies the vacuum Einstein equations with a
cosmological constant that is undetermined. On the other hand, in the "vacuum"
background with no metric, the cohomology is given by a collection of free
scalar- and vector fields. Only certain combinations of linear excitations,
necessarily involving a vector field, can be extended beyond the linear level
with the vector field inducing an Einstein metric.

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The categories of this paper are: nlin
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The categories of this paper are: hep-lat
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The categories of this paper are: atom-ph
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The categories of this paper are: nucl-ex
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The categories of this paper are: stat
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The categories of this paper are: econ
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The categories of this paper are: solv-int
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The categories of this paper are: adap-org
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The categories of this paper are: patt-sol
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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: q-bio
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The categories of this paper are: alg-geom
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The categories of this paper are: nucl-th
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The categories of this paper are: physics
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The categories of this paper are: q-alg