Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Dynamics of finite dimensional non-hermitian systems with indefinite
  metric   We discuss the time evolution of physical finite dimensional systems which
are modelled by non-hermitian Hamiltonians. We address both general
non-hermitian Hamiltonians and pseudo-hermitian ones. We apply the theory of
Krein Spaces to construct metric operators and well-defined inner products. As
an application, we study the stationary behaviour of dissipative One Axis
Twisting Hamiltonians. We discuss the effect of decoherence under different
coupling schemes.

8
The categories of this paper are: hep-ex
29
The categories of this paper are: funct-an
32
The categories of this paper are: atom-ph
11
The categories of this paper are: hep-lat
13
The categories of this paper are: quant-ph
0
The categories of this paper are: hep-ph
21
The categories of this paper are: adap-org
7
The categories of this paper are: hep-th
19
The categories of this paper are: eess
35
The categories of this paper are: mtrl-th
4
The categories of this paper are: cond-mat
33
The categories of this paper are: plasm-ph
22
The categories of this paper are: chao-dyn
9
The categories of this paper are: nlin
1
The categories of this paper are: cs
28
The categories of this paper are: alg-geom