Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Factoring Discrete Quantum Walks on Distance Regular Graphs into
  Continuous Quantum Walks   We consider a discrete quantum walk, called the Grover walk, on a distance
regular graph $X$. Given that $X$ has diameter $d$ and invertible adjacency
matrix, we show that the square of the transition matrix of the Grover walk on
$X$ is a product of at most $d$ commuting transition matrices of continuous
quantum walks, each on some distance digraph of the line digraph of $X$.

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The categories of this paper are: hep-th
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The categories of this paper are: patt-sol
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The categories of this paper are: q-alg
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The categories of this paper are: adap-org
1
The categories of this paper are: cs
31
The categories of this paper are: ao-sci
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The categories of this paper are: supr-con
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The categories of this paper are: hep-lat
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The categories of this paper are: math-ph
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The categories of this paper are: acc-phys
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The categories of this paper are: hep-ex
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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: alg-geom
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The categories of this paper are: cond-mat
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The categories of this paper are: plasm-ph