Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Quantum measurements and Paul traps in gravitational backgrounds   In the present work we solve the motion equations of a particle in a Paul
trap embeded in the gravitational field of a spherically symmetric mass. One of
the ideas behind this work concerns the analysis of the effects that the
gravity--induced quantum noise, stemming from the bodies in the neighborhood of
the Paul trap, could have upon the enhancement of the quantum behavior of this
system. This will be done considering a series expansion for the gravitational
field of the source, and including in the Hamiltonian of the Paul trap only the
first two terms. Higher--order contributions will be introduced as part of the
environment of the system, and in consequence will not appear in the
Hamiltonian. In other words, we put forward an argument that allows us to
differentiate those gravitational degrees of freedom that will appear as an
uncontrollable influence on the Paul trap. Along the ideas of the so called
restricted path integral formalism, we take into account the continuous
monitoring of the position of our particle, and in consequence the
corresponding propagators and probabilities, associated with the different
measurements outputs, are obtained.
  Afterwards, the differential equation related to a quantum nondemolition
variable is posed and solved, i.e., a family of quantum nondemolition
parameters is obtained. Finally, a qualitative analysis of the effects on the
system, of the gravity--induced environment, will be done.

10
The categories of this paper are: q-bio
15
The categories of this paper are: nucl-ex
36
The categories of this paper are: cmp-lg
3
The categories of this paper are: physics
34
The categories of this paper are: chem-ph
14
The categories of this paper are: math-ph
37
The categories of this paper are: supr-con
35
The categories of this paper are: mtrl-th
32
The categories of this paper are: atom-ph
16
The categories of this paper are: stat
6
The categories of this paper are: astro-ph
4
The categories of this paper are: cond-mat
0
The categories of this paper are: hep-ph
8
The categories of this paper are: hep-ex
21
The categories of this paper are: adap-org
9
The categories of this paper are: nlin