Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Neel-VBS phase boundary of the extended J_1-J_2 model with biquadratic
  interaction   The J_1-J_2 model with the biquadratic (plaquette-four-spin) interaction was
simulated with the numerical-diagonalization method. Some limiting cases of
this model have been investigated thoroughly. Taking the advantage of the
extended parameter space, we survey the phase boundary separating the N'eel and
valence-bond-solid phases. According to the deconfined-criticality scenario,
the singularity of this phase boundary is continuous, accompanied with
unconventional critical indices. Diagonalizing the finite-size cluster with N
\le 36 spins, we observe a signature of continuous phase transition. Our
tentative estimate for the correlation-length critical exponent is \nu=1.1(3).
In order to elucidate a non-local character of criticality, we evaluated the
Roomany-Wyld \beta function around the critical point.

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The categories of this paper are: funct-an
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The categories of this paper are: comp-gas
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The categories of this paper are: acc-phys
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The categories of this paper are: hep-th
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The categories of this paper are: hep-lat
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The categories of this paper are: chem-ph
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The categories of this paper are: mtrl-th
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The categories of this paper are: physics
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The categories of this paper are: bayes-an
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The categories of this paper are: hep-ex
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The categories of this paper are: cmp-lg
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The categories of this paper are: solv-int
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The categories of this paper are: math
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The categories of this paper are: nucl-ex
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The categories of this paper are: dg-ga
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The categories of this paper are: math-ph