Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Relativistic short-range correlation effects on the pion dynamics in
  nuclear matter   Replicated theoretical attempts of relativistic approaches to the pion
self-energy in nuclear matter yield unphysical pion spectra. We demonstrate the
crucial dependence of the calculated pion spectra on the correct relativistic
accounting for the short-range correlation effects on the pion self-energy in
the medium. To do this, we simulate the short-range interactions by
phenomenological contact terms in the relativistic Lagrangian density, and
derive the pion self-energy by carefully taking into account the relativistic
kinematics. The obtained spectrum for the pion-like excitations in cold nuclear
matter shows physically meaningful branches, in contrast to those obtained
before by different authors by the use of simplified relativistic approaches to
the short-range correlations.

27
The categories of this paper are: comp-gas
33
The categories of this paper are: plasm-ph
22
The categories of this paper are: chao-dyn
3
The categories of this paper are: physics
11
The categories of this paper are: hep-lat
30
The categories of this paper are: q-alg
6
The categories of this paper are: astro-ph
28
The categories of this paper are: alg-geom
35
The categories of this paper are: mtrl-th
23
The categories of this paper are: solv-int
20
The categories of this paper are: acc-phys
16
The categories of this paper are: stat
1
The categories of this paper are: cs
5
The categories of this paper are: gr-qc
9
The categories of this paper are: nlin
10
The categories of this paper are: q-bio