Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Stationary states of a PT-symmetric two-mode Bose-Einstein condensate   The understanding of nonlinear PT-symmetric quantum systems, arising for
example in the theory of Bose-Einstein condensates in PT-symmetric potentials,
is widely based on numerical investigations, and little is known about generic
features induced by the interplay of PT-symmetry and nonlinearity. To gain
deeper insights it is important to have analytically solvable toy-models at
hand. In the present paper the stationary states of a simple toy-model of a
PT-symmetric system are investigated. The model can be interpreted as a simple
description of a Bose-Einstein condensate in a PT-symmetric double well trap in
a two-mode approximation. The eigenvalues and eigenstates of the system can be
explicitly calculated in a straight forward manner; the resulting structures
resemble those that have recently been found numerically for a more realistic
PT-symmetric double delta potential. In addition, a continuation of the system
is introduced that allows an interpretation in terms of a simple linear matrix
model.

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The categories of this paper are: cs
30
The categories of this paper are: q-alg
20
The categories of this paper are: acc-phys
27
The categories of this paper are: comp-gas
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The categories of this paper are: ao-sci
3
The categories of this paper are: physics
21
The categories of this paper are: adap-org
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The categories of this paper are: chem-ph
0
The categories of this paper are: hep-ph
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The categories of this paper are: math
36
The categories of this paper are: cmp-lg
10
The categories of this paper are: q-bio
35
The categories of this paper are: mtrl-th
5
The categories of this paper are: gr-qc
12
The categories of this paper are: nucl-th
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The categories of this paper are: stat