Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Level curvatures, spectral statistics and scaling for interacting
  particles   The mobility of two interacting particles in a random potential is studied,
using the sensitivity of their levels to a change of boundary conditions. The
delocalization in Hilbert space induced by the interaction of the two particle
Fock states is shown to decrease the mobility in metals and to increase it in
insulators. In contrast to the single particle case, the spectral rigidity is
not directly related to the level curvature. Therefore, another curvature of
topological origin is introduced, which defines the energy scale below which
the spectrum has the universal Wigner-Dyson rigidity.

32
The categories of this paper are: atom-ph
13
The categories of this paper are: quant-ph
15
The categories of this paper are: nucl-ex
20
The categories of this paper are: acc-phys
31
The categories of this paper are: ao-sci
37
The categories of this paper are: supr-con
27
The categories of this paper are: comp-gas
25
The categories of this paper are: patt-sol
1
The categories of this paper are: cs
35
The categories of this paper are: mtrl-th
19
The categories of this paper are: eess
36
The categories of this paper are: cmp-lg
23
The categories of this paper are: solv-int
12
The categories of this paper are: nucl-th
7
The categories of this paper are: hep-th
34
The categories of this paper are: chem-ph