Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: K-essence Emergent Spacetime as Generalized Vaidya Geometry   We establish a formal connection between the {\bf K}-essence emergent gravity
scenario and generalizations of Vaidya spacetime. Choosing the {\bf K}-essence
action to be of the Dirac-Born-Infeld variety, the physical spacetime to be a
general static spherically symmetric black hole and restricting the {\bf
K}-essence scalar field to be a function solely of the advanced or the retarded
time, we show that the emergent gravity metric resembles closely the
generalized Vaidya metrics for null fluid collapse proposed by Husain. Imposing
null energy conditions on the emergent energy-momentum tensor derived from the
emergent Einstein equation, restrictions are obtained on the functions
characterizing the emergent metric for consistent identification with
generalized Vaidya spacetimes. We discuss the possibility of dynamical horizons
in the {\bf K-}essence emergent Vaidya spacetime. Admissible explicit black
hole background metrics are discussed as examples.

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The categories of this paper are: comp-gas
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The categories of this paper are: math
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The categories of this paper are: hep-ex
32
The categories of this paper are: atom-ph
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The categories of this paper are: nlin
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The categories of this paper are: eess
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The categories of this paper are: cmp-lg
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The categories of this paper are: acc-phys
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The categories of this paper are: bayes-an
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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: solv-int
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The categories of this paper are: q-alg
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The categories of this paper are: chem-ph
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The categories of this paper are: patt-sol
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The categories of this paper are: mtrl-th