Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Quantum trajectories   This paper presents a new approach to phase space trajectories in quantum
mechanics. A Moyal description of quantum theory is used, where observables and
states are treated as classical functions on a classical phase space. A quantum
trajectory being an appropriate solution to quantum Hamiltonian equations is
also a function defined on a classical phase space. The difference, when
compare with classical theory, is in a deformation of a classical action of a
flow on observables and states to an appropriate quantum action. This leads
also to deformation of a multiplication rule for any quantum trajectory treated
as a one-parameter group of diffeomorphisms. Moreover, several examples are
given, presenting the developed formalism for particular quantum systems.

11
The categories of this paper are: hep-lat
27
The categories of this paper are: comp-gas
24
The categories of this paper are: dg-ga
30
The categories of this paper are: q-alg
20
The categories of this paper are: acc-phys
23
The categories of this paper are: solv-int
1
The categories of this paper are: cs
19
The categories of this paper are: eess
37
The categories of this paper are: supr-con
6
The categories of this paper are: astro-ph
28
The categories of this paper are: alg-geom
22
The categories of this paper are: chao-dyn
26
The categories of this paper are: bayes-an
7
The categories of this paper are: hep-th
3
The categories of this paper are: physics
16
The categories of this paper are: stat