Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Operational quasiprobabilities for qudits   We propose an operational quasiprobability function for qudits, enabling a
comparison between quantum and hidden-variable theories. We show that the
quasiprobability function becomes positive semidefinite if consecutive
measurement results are described by a hidden-variable model with locality and
noninvasive measurability assumed. Otherwise, it is negative valued. The
negativity depends on the observables to be measured as well as a given state,
as the quasiprobability function is operationally defined. We also propose a
marginal quasiprobability function and show that it plays the role of an
entanglement witness for two qudits. In addition, we discuss an optical
experiment of a polarization qubit to demonstrate its nonclassicality in terms
of the quasiprobability function.

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The categories of this paper are: cond-mat
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The categories of this paper are: nucl-ex
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The categories of this paper are: ao-sci
33
The categories of this paper are: plasm-ph
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The categories of this paper are: eess
36
The categories of this paper are: cmp-lg
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The categories of this paper are: cs
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The categories of this paper are: math
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The categories of this paper are: gr-qc
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The categories of this paper are: nlin
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The categories of this paper are: solv-int
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The categories of this paper are: astro-ph
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The categories of this paper are: econ
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The categories of this paper are: acc-phys
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The categories of this paper are: comp-gas
35
The categories of this paper are: mtrl-th