Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Can the Nambu-Goldstone Boson Live on the Light-Front?   We show that the Nambu-Goldstone(NG) boson restricted on the light-front(LF)
can only exist if we regularize the theory by introducing the explicit breaking
NG-boson mass $m_{\pi}$. The NG-boson zero mode, when integrated over the LF,
must have a singular behavior $\sim 1/m^2_{\pi}$ in the symmetric limit of
$m^2_{\pi}\rightarrow 0$. In the discretized LF quantization this peculiarity
is clarified in terms of the zero-mode constraints in the linear $\sigma$
model. The LF charge annihilates the vacuum, while it is not conserved in the
symmetric limit in the NG phase.

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The categories of this paper are: nucl-th
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The categories of this paper are: econ
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The categories of this paper are: adap-org
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The categories of this paper are: patt-sol
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The categories of this paper are: bayes-an
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The categories of this paper are: comp-gas
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The categories of this paper are: cmp-lg
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The categories of this paper are: gr-qc
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The categories of this paper are: q-bio
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The categories of this paper are: nlin
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The categories of this paper are: q-alg
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The categories of this paper are: chem-ph
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The categories of this paper are: q-fin
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The categories of this paper are: mtrl-th
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The categories of this paper are: ao-sci
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The categories of this paper are: chao-dyn