Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Response functions and superfluid density in a weakly interacting Bose
  gas with non-quadratic dispersion   Motivated by the experimental search for Bose condensation of quasiparticles
in semiconductors, the response functions of a weakly interacting Bose gas,
with isotropic but non-quadratic dispersion, are considered. Non-quadratic
dispersion modifies the definition of particle current, and leads to modified
sum rules for the current-current response function. The effect of these
modifications on the Berezhinski-Kosterlitz-Thouless transition is discussed.

9
The categories of this paper are: nlin
15
The categories of this paper are: nucl-ex
36
The categories of this paper are: cmp-lg
33
The categories of this paper are: plasm-ph
2
The categories of this paper are: math
5
The categories of this paper are: gr-qc
18
The categories of this paper are: econ
1
The categories of this paper are: cs
23
The categories of this paper are: solv-int
34
The categories of this paper are: chem-ph
25
The categories of this paper are: patt-sol
10
The categories of this paper are: q-bio
37
The categories of this paper are: supr-con
20
The categories of this paper are: acc-phys
26
The categories of this paper are: bayes-an
8
The categories of this paper are: hep-ex