Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The observables of a dissipative quantum system   A time-dependent product is introduced between the observables of a
dissipative quantum system, that accounts for the effects of dissipation on
observables and commutators. In the $t \to \infty$ limit this yields a
contracted algebra. The general ideas are corroborated by a few explicit
examples.

28
The categories of this paper are: alg-geom
16
The categories of this paper are: stat
27
The categories of this paper are: comp-gas
6
The categories of this paper are: astro-ph
12
The categories of this paper are: nucl-th
30
The categories of this paper are: q-alg
1
The categories of this paper are: cs
4
The categories of this paper are: cond-mat
20
The categories of this paper are: acc-phys
22
The categories of this paper are: chao-dyn
8
The categories of this paper are: hep-ex
29
The categories of this paper are: funct-an
7
The categories of this paper are: hep-th
33
The categories of this paper are: plasm-ph
24
The categories of this paper are: dg-ga
26
The categories of this paper are: bayes-an