Possible production of "collapsed" hadronic matter in very-high-energy nucleon-nucleon collisions

We speculate on the possible production of "collapsed" hadrons, i.e., color-singlet, electrically uncharged (or with small integral charge) clusters of quarks and antiquarks, in very-high-energy proton-proton collisions, the intermediate states of which contain relatively large numbers of quarks $q$, antiquarks $\overline{q}$, and gluons $g$. Using a thermodynamic model, we crudely estimate the numbers and kinetic energies of the $q$, $\overline{q}$, and $g$ in the intermediatestate gas mixture, and indicate how the properties of collapsed hadrons might depend on the quantum numbers of the $q$ and $\overline{q}$. A brief discussion of experimental signatures for identification of collapsed hadrons is presented, along with mention of the consequences of possible collapsed-hadron production in the early Universe.