Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: On the relation between Euclidean and real time calculations of Green
  functions at finite temperature   We find a relation between the semiclassical approximation of the temperature
(Matsubara) 2-point correlator and the corresponding classical Green function
in real time at finite temperature. The anharmonic oscillator at finite
temperature is used to illustrate our statement, which is however of rather
general origin.

17
The categories of this paper are: q-fin
36
The categories of this paper are: cmp-lg
7
The categories of this paper are: hep-th
19
The categories of this paper are: eess
22
The categories of this paper are: chao-dyn
23
The categories of this paper are: solv-int
26
The categories of this paper are: bayes-an
28
The categories of this paper are: alg-geom
5
The categories of this paper are: gr-qc
2
The categories of this paper are: math
30
The categories of this paper are: q-alg
9
The categories of this paper are: nlin
4
The categories of this paper are: cond-mat
29
The categories of this paper are: funct-an
37
The categories of this paper are: supr-con
12
The categories of this paper are: nucl-th