Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Ground state energy of an interacting electron system in the background
  of two opposite magnetic strings   Motivated by our earlier work, we show in this paper rigorously that the
ground state energy and degeneracy of an infinitely extended system of
interacting electrons in the background of a homogeneous magnetic field and two
separated magnetic strings of opposite strength is the same as for the system
without strings. By using symmetry considerations we obtain further that the
energy spectrum does not depend on the string separation distance for strictly
positive distances. As a side effect of our considerations, we obtain a virial
theorem for the two string system in the case of a homogeneous interaction
potential which has the same form as the virial theorem without the strings.

11
The categories of this paper are: hep-lat
24
The categories of this paper are: dg-ga
23
The categories of this paper are: solv-int
1
The categories of this paper are: cs
33
The categories of this paper are: plasm-ph
37
The categories of this paper are: supr-con
2
The categories of this paper are: math
32
The categories of this paper are: atom-ph
34
The categories of this paper are: chem-ph
14
The categories of this paper are: math-ph
26
The categories of this paper are: bayes-an
30
The categories of this paper are: q-alg
17
The categories of this paper are: q-fin
3
The categories of this paper are: physics
9
The categories of this paper are: nlin
16
The categories of this paper are: stat