Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Fermion condensation: a strange idea successfully explaining behavior of
  numerous objects in Nature   Strongly correlated Fermi systems are among the most intriguing, best
experimentally studied and fundamental systems in physics. These are, however,
in defiance of theoretical understanding. The ideas based on the concepts like
Kondo lattice and involving quantum and thermal fluctuations at a quantum
critical point have been used to explain the unusual physics. Alas, being
suggested to describe one property, these approaches fail to explain the
others. This means a real crisis in theory suggesting that there is a hidden
fundamental law of nature, which remains to be recognized. A theory of fermion
condensation quantum phase transition, preserving the extended quasiparticles
paradigm and intimately related to unlimited growth of the effective mass as a
function of temperature, magnetic field etc, is capable to resolve the problem.
We discuss the construction of the theory and show that it delivers theoretical
explanations of vast majority of experimental results in strongly correlated
systems such as heavy-fermion metals and quasi-two-dimensional Fermi systems.

30
The categories of this paper are: q-alg
5
The categories of this paper are: gr-qc
37
The categories of this paper are: supr-con
7
The categories of this paper are: hep-th
2
The categories of this paper are: math
15
The categories of this paper are: nucl-ex
26
The categories of this paper are: bayes-an
29
The categories of this paper are: funct-an
32
The categories of this paper are: atom-ph
33
The categories of this paper are: plasm-ph
20
The categories of this paper are: acc-phys
10
The categories of this paper are: q-bio
13
The categories of this paper are: quant-ph
35
The categories of this paper are: mtrl-th
36
The categories of this paper are: cmp-lg
24
The categories of this paper are: dg-ga