Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Finite temperature correlations in the one-dimensional quantum Ising
  model   We extend the form-factors approach to the quantum Ising model at finite
temperature. The two point function of the energy is obtained in closed form,
while the two point function of the spin is written as a Fredholm determinant.
Using the approach of \Korbook, we obtain, starting directly from the continuum
formulation, a set of six differential equations satisfied by this two point
function. Four of these equations involve only spacetime derivatives, of which
three are equivalent to the equations obtained earlier in \mccoy,\perk. In
addition, we obtain two new equations involving a temperature derivative. Some
of these results are generalized to the Ising model on the half line with a
magnetic field at the origin.

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The categories of this paper are: physics
22
The categories of this paper are: chao-dyn
18
The categories of this paper are: econ
30
The categories of this paper are: q-alg
33
The categories of this paper are: plasm-ph
17
The categories of this paper are: q-fin
26
The categories of this paper are: bayes-an
15
The categories of this paper are: nucl-ex
25
The categories of this paper are: patt-sol
16
The categories of this paper are: stat
34
The categories of this paper are: chem-ph
19
The categories of this paper are: eess
12
The categories of this paper are: nucl-th
14
The categories of this paper are: math-ph
36
The categories of this paper are: cmp-lg
31
The categories of this paper are: ao-sci