Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Wormholes, Gamma Ray Bursts and the Amount of Negative Mass in the
  Universe   In this essay, we assume that negative mass objects can exist in the
extragalactic space and analyze the consequences of their microlensing on light
from distant Active Galactic Nuclei. We find that such events have very similar
features to some observed Gamma Ray Bursts and use recent satellite data to set
an upper bound to the amount of negative mass in the universe.

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The categories of this paper are: alg-geom
10
The categories of this paper are: q-bio
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The categories of this paper are: dg-ga
6
The categories of this paper are: astro-ph
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The categories of this paper are: solv-int
17
The categories of this paper are: q-fin
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The categories of this paper are: chem-ph
3
The categories of this paper are: physics
9
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: adap-org
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The categories of this paper are: stat
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The categories of this paper are: acc-phys
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The categories of this paper are: econ
19
The categories of this paper are: eess
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The categories of this paper are: mtrl-th