Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Quantum-Monte-Carlo Calculations for Bosons in a Two-Dimensional
  Harmonic Trap   Path-Integral-Monte-Carlo simulation has been used to calculate the
properties of a two-dimensional (2D) interacting Bose system. The bosons
interact with hard-core potentials and are confined to a harmonic trap. Results
for the density profiles, the condensate fraction, and the superfluid density
are presented. By comparing with the ideal gas we easily observe the effects of
finite size and the depletion of the condensate because of interactions. The
system is known to have no phase transition to a Bose-Einstein condensation in
2D, but the finite system shows that a significant fraction of the particles
are in the lowest state at low temperatures.

28
The categories of this paper are: alg-geom
23
The categories of this paper are: solv-int
18
The categories of this paper are: econ
19
The categories of this paper are: eess
1
The categories of this paper are: cs
35
The categories of this paper are: mtrl-th
21
The categories of this paper are: adap-org
32
The categories of this paper are: atom-ph
25
The categories of this paper are: patt-sol
13
The categories of this paper are: quant-ph
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The categories of this paper are: comp-gas
0
The categories of this paper are: hep-ph
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The categories of this paper are: ao-sci
16
The categories of this paper are: stat
34
The categories of this paper are: chem-ph
11
The categories of this paper are: hep-lat