2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/179790We consider the lightest scalar meson in the frame of the $SU_L(2)\times SU_R(2)$ linear $σ$ model, keeping in mind that this model could be the low energy realization of the two-flavour QCD. We show that the $σ$ field is described by its four-quark component at least in the $σ$ resonance energy (virtuality) region and the $σ\toγγ$ decay is the four quark transition. We emphasize that residues of the $σ$ pole in the $ππ\toππ$ and $γγ\toππ$ amplitudes do not give an idea about the $σ$ meson nature, and the progress in studying the $σ$ meson production mechanisms in different processes could essentially further us in understanding its nature.10 pages, 3 figures, English improved, PACS numbers changed, two Refs. added, E-mail addresses removed and Ref. [1] shortened for the overrun of the article length allowable in Phys. Rev. LettHigh Energy Physics - PhenomenologyHigh Energy Physics - ExperimentNuclear Theorytext