Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Off-diagonal Bethe ansatz and exact solution of a topological spin ring   A general method is proposed for constructing the Bethe ansatz equations of
integrable models without U(1) symmetry. As an example, the exact spectrum of
the XXZ spin ring with M{\" o}bius like topological boundary condition is
derived by constructing a modified T-Q relation based on the functional
connection between the eigenvalues of the transfer matrix and the quantum
determinant of the monodromy matrix. With the exact solution, the elementary
excitations of the topological XX spin ring is discussed in detail. It is found
that the excitation spectrum indeed shows a nontrivial topological nature.

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The categories of this paper are: physics
31
The categories of this paper are: ao-sci
12
The categories of this paper are: nucl-th
1
The categories of this paper are: cs
27
The categories of this paper are: comp-gas
34
The categories of this paper are: chem-ph
18
The categories of this paper are: econ
19
The categories of this paper are: eess
16
The categories of this paper are: stat
35
The categories of this paper are: mtrl-th
26
The categories of this paper are: bayes-an
29
The categories of this paper are: funct-an
11
The categories of this paper are: hep-lat
33
The categories of this paper are: plasm-ph
22
The categories of this paper are: chao-dyn
30
The categories of this paper are: q-alg