Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Quantum History cannot be Copied   We show that unitarity does not allow cloning of any two points in a ray.
This has implication for cloning of the geometric phase information in a
quantum state. In particular, the quantum history which is encoded in the
geometric phase during cyclic evolution of a quantum system cannot be copied.
We also prove that the generalized geometric phase information cannot be copied
by a unitary operation. We argue that our result also holds in the consistent
history formulation of quantum mechanics.

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The categories of this paper are: physics
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The categories of this paper are: acc-phys
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The categories of this paper are: astro-ph
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The categories of this paper are: comp-gas
31
The categories of this paper are: ao-sci
10
The categories of this paper are: q-bio
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The categories of this paper are: hep-ex
29
The categories of this paper are: funct-an
0
The categories of this paper are: hep-ph
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The categories of this paper are: nucl-th
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The categories of this paper are: chao-dyn
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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: eess
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The categories of this paper are: hep-lat
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The categories of this paper are: cond-mat