Mitja Rosina: The sigma meson in QCD


Outline
Motivation
Two-level Nambu Jona-Lasino with one flavour
The quasispin NJL-like model
Relation to lattice calculations
The N -> infty limit
The spectrum of 0- and 0+ exciations
Emergence of sigma meson
Extraction of pion-pion scattering length
Results for N=192
Scattering length
Conclusion