Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The undecidability of joint embedding and joint homomorphism for
  hereditary graph classes   We prove that the joint embedding property is undecidable for hereditary
graph classes, via a reduction from the tiling problem. The proof is then
adapted to show the undecidability of the joint homomorphism property as well.

30
The categories of this paper are: q-alg
12
The categories of this paper are: nucl-th
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The categories of this paper are: stat
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The categories of this paper are: q-fin
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The categories of this paper are: alg-geom
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The categories of this paper are: ao-sci
21
The categories of this paper are: adap-org
5
The categories of this paper are: gr-qc
13
The categories of this paper are: quant-ph
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The categories of this paper are: plasm-ph
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The categories of this paper are: cmp-lg
6
The categories of this paper are: astro-ph
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The categories of this paper are: acc-phys
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The categories of this paper are: solv-int
1
The categories of this paper are: cs
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The categories of this paper are: math-ph