Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Time-propagation of the Kadanoff-Baym equations for inhomogeneous
  systems   We have developed a time propagation scheme for the Kadanoff-Baym equations
for general inhomogeneous systems. These equations describe the time evolution
of the nonequilibrium Green function for interacting many-body systems in the
presence of time-dependent external fields. The external fields are treated
nonperturbatively whereas the many-body interactions are incorporated
perturbatively using Phi-derivable self-energy approximations that guarantee
the satisfaction of the macroscopic conservation laws of the system. These
approximations are discussed in detail for the time-dependent Hartree-Fock, the
second Born and the GW approximation.

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The categories of this paper are: eess
8
The categories of this paper are: hep-ex
16
The categories of this paper are: stat
36
The categories of this paper are: cmp-lg
35
The categories of this paper are: mtrl-th
13
The categories of this paper are: quant-ph
26
The categories of this paper are: bayes-an
11
The categories of this paper are: hep-lat
23
The categories of this paper are: solv-int
14
The categories of this paper are: math-ph
10
The categories of this paper are: q-bio
32
The categories of this paper are: atom-ph
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The categories of this paper are: comp-gas
1
The categories of this paper are: cs
34
The categories of this paper are: chem-ph
31
The categories of this paper are: ao-sci