Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A stochastic golden rule and quantum Langevin equation for the low
  density limit   A rigorous derivation of quantum Langevin equation from microscopic dynamics
in the low density limit is given. We consider a quantum model of a microscopic
system (test particle) coupled with a reservoir (gas of light Bose particles)
via interaction of scattering type. We formulate a mathematical procedure (the
so-called stochastic golden rule) which allows us to determine the quantum
Langevin equation in the limit of large time and small density of particles of
the reservoir. The quantum Langevin equation describes not only dynamics of the
system but also the reservoir. We show that the generator of the corresponding
master equation has the Lindblad form of most general generators of completely
positive semigroups.

25
The categories of this paper are: patt-sol
22
The categories of this paper are: chao-dyn
5
The categories of this paper are: gr-qc
27
The categories of this paper are: comp-gas
3
The categories of this paper are: physics
18
The categories of this paper are: econ
15
The categories of this paper are: nucl-ex
19
The categories of this paper are: eess
21
The categories of this paper are: adap-org
10
The categories of this paper are: q-bio
11
The categories of this paper are: hep-lat
30
The categories of this paper are: q-alg
26
The categories of this paper are: bayes-an
37
The categories of this paper are: supr-con
35
The categories of this paper are: mtrl-th
8
The categories of this paper are: hep-ex