Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Non-Markovian Quantum Feedback Networks II: Controlled Flows   The concept of a controlled flow of a dynamical system, especially when the
controlling process feeds information back about the system, is of central
importance in control engineering. In this paper we build on the ideas
presented by Bouten and van Handel (L. Bouten, R. van Handel, "On the
separation principle of quantum control", in Quantum Stochastics and
Information: Statistics, Filtering and Control, World Scientific, 2008) and
develop a general theory of quantum feedback. We elucidate the relationship
between the controlling processes $Z$ and the measured process $Y$, and to this
end make a distinction between what we call the input picture and the output
picture. We should that the input-output relations for the noise fields have
additional terms not present in the standard theory, but that the relationship
between the control processes and measured processes themselves are internally
consistent - we do this for the two main cases of quadrature measurement and
photon-counting measurement. The theory is general enough to include a
modulating filter which processes the measurement readout $Y$ before returning
to the system. This opens up the prospect of applying very general engineering
feedback control techniques to open quantum systems in a systematic manner, and
we consider a number of specific modulating filter problems. Finally, we give a
brief argument as to why most of the rules for making instantaneous feedback
connections (J. Gough, M.R. James, "Quantum Feedback Networks: Hamiltonian
Formulation", Commun. Math. Phys., 287, 1109, 2009) ought to apply for
controlled dynamical networks as well.

18
The categories of this paper are: econ
23
The categories of this paper are: solv-int
28
The categories of this paper are: alg-geom
16
The categories of this paper are: stat
10
The categories of this paper are: q-bio
20
The categories of this paper are: acc-phys
32
The categories of this paper are: atom-ph
3
The categories of this paper are: physics
0
The categories of this paper are: hep-ph
37
The categories of this paper are: supr-con
24
The categories of this paper are: dg-ga
17
The categories of this paper are: q-fin
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The categories of this paper are: adap-org
8
The categories of this paper are: hep-ex
25
The categories of this paper are: patt-sol
4
The categories of this paper are: cond-mat