Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Effective mass suppression in a ferromagnetic two-dimensional electron
  liquid   We present numerical calculations of the electron effective mass in an
interacting, ferromagnetic, two-dimensional electron system. We consider
quantum interaction effects associated with the charge-density fluctuation
induced many-body vertex corrections. Our theory, which is free of adjustable
parameters, reveals that the effective mass is suppressed (relative to its band
value) in the strong coupling limit, in good agreement with the results of
recent experimental measurements.

19
The categories of this paper are: eess
17
The categories of this paper are: q-fin
34
The categories of this paper are: chem-ph
20
The categories of this paper are: acc-phys
36
The categories of this paper are: cmp-lg
3
The categories of this paper are: physics
24
The categories of this paper are: dg-ga
25
The categories of this paper are: patt-sol
10
The categories of this paper are: q-bio
21
The categories of this paper are: adap-org
7
The categories of this paper are: hep-th
37
The categories of this paper are: supr-con
30
The categories of this paper are: q-alg
18
The categories of this paper are: econ
14
The categories of this paper are: math-ph
9
The categories of this paper are: nlin