Color-Singlet and Color-Octet Quark Matters

Abstract

Quarks and antiquarks carry color and electric charges and belong to the color-triplet $3$ group and the color-antitriplet $\bar{3}$ group respectively. The product groups of $3$ and $\bar{3}$ consist of the color-singlet $1$ and the color-octet $8$ subgroups. Therefore, quarks and antiquarks combine to form color-singlet $[q\bar{q}{]}^1$ quark matter and color-octet $[q\bar{q}{]}^8$ quark matter. The color-octet quark matter corresponds to the $q\bar{q}$ quark matter as envisaged in the realm of present knowledge but the color-singlet quark matter is as yet unexplored and now submitted for exploration. The color-singlet quark matter with two flavors can be separated into charged and neutral color-singlet quark matters. In the neutral color-singlet quark matter, the quark and the antiquark interacting only in the QED interaction may form stable and confined colorless QED mesons non-perturbatively at about 17 MeV and 38 MeV (PRC81,064903(2010) and JHEP(2020(8),165). It is proposed that the possible existence of the QED mesons may be a signature of the neutral color-singlet quark matter at $T=0$. The observations of the anomalous soft photons at CERN, and the anomalous bosons with mass about 17 MeV at ATOMKI, DUBNA, and HUS, and mass about 38 MeV at DUBNA hold promising experimental evidence for the existence of such QED mesons, pending further confirmations.

Comments: 15 pages, 7 figures, talk presented at the International Conference in High Energy Physics, Batumi, Georgia, September 15-19, 2025