Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Physical Realizability of Multi-Level Quantum Systems   This paper considers the physical realizability condition for multi-level
quantum systems having polynomial Hamiltonian and multiplicative coupling with
respect to several interacting boson fields. Specifically, it generalizes a
recent result the authors developed for two-level quantum systems. For this
purpose, the algebra of SU(n) was incorporated. As a consequence, the obtained
condition is given in terms of the structure constants of SU(n).

11
The categories of this paper are: hep-lat
7
The categories of this paper are: hep-th
18
The categories of this paper are: econ
6
The categories of this paper are: astro-ph
37
The categories of this paper are: supr-con
10
The categories of this paper are: q-bio
3
The categories of this paper are: physics
25
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: solv-int
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The categories of this paper are: chao-dyn
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The categories of this paper are: dg-ga
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The categories of this paper are: nucl-ex
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The categories of this paper are: math-ph
36
The categories of this paper are: cmp-lg
32
The categories of this paper are: atom-ph