Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Symmetry breaking in self-consistent models: Lessons from an exactly
  solvable many-fermion model   This work presents a many-fermion Hamiltonian with the following properties:
1) is exactly solvable, 2) has a second order insulator-metal quantum phase
transition, 3) has a well defined mean field approximation and 4) its
mean-field ground state displays a liquid-solid transition. The phenomenon of
symmetry breaking in fermionic self-consistent models is discussed in the light
of these remarkable properties of the many-body model.

23
The categories of this paper are: solv-int
33
The categories of this paper are: plasm-ph
18
The categories of this paper are: econ
15
The categories of this paper are: nucl-ex
16
The categories of this paper are: stat
32
The categories of this paper are: atom-ph
31
The categories of this paper are: ao-sci
21
The categories of this paper are: adap-org
27
The categories of this paper are: comp-gas
17
The categories of this paper are: q-fin
11
The categories of this paper are: hep-lat
34
The categories of this paper are: chem-ph
30
The categories of this paper are: q-alg
24
The categories of this paper are: dg-ga
6
The categories of this paper are: astro-ph
22
The categories of this paper are: chao-dyn