Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Universal Scaling of the Conductivity at the Superfluid-Insulator Phase
  Transition   The scaling of the conductivity at the superfluid-insulator quantum phase
transition in two dimensions is studied by numerical simulations of the
Bose-Hubbard model. In contrast to previous studies, we focus on properties of
this model in the experimentally relevant thermodynamic limit at finite
temperature T. We find clear evidence for deviations from w_k-scaling of the
conductivity towards w_k/T-scaling at low Matsubara frequencies w_k. By careful
analytic continuation using Pade approximants we show that this behavior
carries over to the real frequency axis where the conductivity scales with w/T
at small frequencies and low temperatures. We estimate the universal dc
conductivity to be 0.45(5)Q^2/h, distinct from previous estimates in the T=0,
w/T >> 1 limit.

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The categories of this paper are: stat
32
The categories of this paper are: atom-ph
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The categories of this paper are: ao-sci
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The categories of this paper are: econ
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The categories of this paper are: nlin
11
The categories of this paper are: hep-lat
33
The categories of this paper are: plasm-ph
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The categories of this paper are: q-alg
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The categories of this paper are: bayes-an
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The categories of this paper are: nucl-ex
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The categories of this paper are: comp-gas
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The categories of this paper are: quant-ph
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The categories of this paper are: eess
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The categories of this paper are: alg-geom
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The categories of this paper are: chem-ph
8
The categories of this paper are: hep-ex