Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Collective modes in quantum electron glasses and electron-assisted
  hopping   We study electronic transport in Anderson insulators with strong Coulomb
interactions in dimensions d>=2. Close to the metal insulator transition where
the single particle localization length is much larger than
interparticle-distance, the interactions lead to a strongly correlated quantum
glass phase. Even though single particle excitations are localized and the
system is insulating, there are collective electronic modes which remain
delocalized down to parametrically small energies. These collective excitations
serve as a continuous bath which can provide the activation energy for variable
range hopping transport. This circumvents the energy conservation problem
arising when only discrete particle-hole excitations are present. In contrast
to the weak and material-dependent phonon-assisted hopping mechanism, the
activation by an electronic bath leads to a nearly universal prefactor e^2/h of
the Efros-Shklovskii conductance, as is observed in many recent experiments.

12
The categories of this paper are: nucl-th
27
The categories of this paper are: comp-gas
14
The categories of this paper are: math-ph
1
The categories of this paper are: cs
35
The categories of this paper are: mtrl-th
0
The categories of this paper are: hep-ph
9
The categories of this paper are: nlin
22
The categories of this paper are: chao-dyn
15
The categories of this paper are: nucl-ex
10
The categories of this paper are: q-bio
24
The categories of this paper are: dg-ga
7
The categories of this paper are: hep-th
5
The categories of this paper are: gr-qc
8
The categories of this paper are: hep-ex
25
The categories of this paper are: patt-sol
36
The categories of this paper are: cmp-lg