Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Intersecting hypersurfaces in AdS and Lovelock gravity   Colliding and intersecting hypersurfaces filled with matter (membranes) are
studied in the Lovelock higher order curvature theory of gravity. Lovelock
terms couple hypersurfaces of different dimensionalities, extending the range
of possible intersection configurations. We restrict the study to constant
curvature membranes in constant curvature AdS and dS background and consider
their general intersections. This illustrates some key features which make the
theory different to the Einstein gravity. Higher co-dimension membranes may lie
at the intersection of co-dimension 1 hypersurfaces in Lovelock gravity; the
hypersurfaces are located at the discontinuities of the first derivative of the
metric, and they need not carry matter.
  The example of colliding membranes shows that general solutions can only be
supported by (spacelike) matter at the collision surface, thus naturally
conflicting with the dominant energy condition (DEC). The imposition of the DEC
gives selection rules on the types of collision allowed.
  When the hypersurfaces don't carry matter, one gets a soliton-like
configuration. Then, at the intersection one has a co-dimension 2 or higher
membrane standing alone in AdS-vacuum spacetime \emph{without conical
singularities.}
  Another result is that if the number of intersecting hypersurfaces goes to
infinity the limiting spacetime is free of curvature singularities if the
intersection is put at the boundary of each AdS bulk.

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The categories of this paper are: nucl-ex
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The categories of this paper are: hep-lat
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The categories of this paper are: astro-ph
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The categories of this paper are: atom-ph
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The categories of this paper are: chem-ph
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The categories of this paper are: quant-ph
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The categories of this paper are: nlin
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The categories of this paper are: econ
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The categories of this paper are: supr-con
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The categories of this paper are: q-fin
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The categories of this paper are: physics
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The categories of this paper are: alg-geom
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The categories of this paper are: bayes-an
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The categories of this paper are: eess
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The categories of this paper are: dg-ga
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The categories of this paper are: comp-gas