Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Controllability of the discrete-spectrum Schrodinger equation driven by
  an external field   We prove approximate controllability of the bilinear Schr\"odinger equation
in the case in which the uncontrolled Hamiltonian has discrete non-resonant
spectrum. The results that are obtained apply both to bounded or unbounded
domains and to the case in which the control potential is bounded or unbounded.
The method relies on finite-dimensional techniques applied to the Galerkin
approximations and permits, in addition, to get some controllability properties
for the density matrix. Two examples are presented: the harmonic oscillator and
the 3D well of potential, both controlled by suitable potentials.

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The categories of this paper are: supr-con
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The categories of this paper are: nucl-ex
14
The categories of this paper are: math-ph
9
The categories of this paper are: nlin
4
The categories of this paper are: cond-mat
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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: solv-int
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The categories of this paper are: econ
20
The categories of this paper are: acc-phys
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The categories of this paper are: plasm-ph
3
The categories of this paper are: physics
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The categories of this paper are: cmp-lg
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The categories of this paper are: eess
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The categories of this paper are: ao-sci
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The categories of this paper are: alg-geom