Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Low-lying excitations in one-dimensional lattice electron systems   We consider a general one-dimensional tight-binding electron model which has
a period $P$. For any filling factor $\nu$ such that $P\nu$ is non-integral, we
prove that the model in the infinite volume limit has either a symmetry
breaking or a unique ground state with gapless excitations. The proof is based
on the idea of Yamanaka, Oshikawa and Affleck (cond-mat/9701141), who extended
the Lieb-Schultz-Mattis argument to electron systems.

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The categories of this paper are: acc-phys
9
The categories of this paper are: nlin
16
The categories of this paper are: stat
32
The categories of this paper are: atom-ph
15
The categories of this paper are: nucl-ex
24
The categories of this paper are: dg-ga
5
The categories of this paper are: gr-qc
3
The categories of this paper are: physics
21
The categories of this paper are: adap-org
6
The categories of this paper are: astro-ph
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The categories of this paper are: chem-ph
31
The categories of this paper are: ao-sci
26
The categories of this paper are: bayes-an
7
The categories of this paper are: hep-th
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The categories of this paper are: alg-geom
12
The categories of this paper are: nucl-th