  It is entirely plausible that during the primordial quark-hadron transition,
microseconds after the Big Bang, the universe may experience supercooling
accompanied by mini inflation leading to a first-order phase transition from
quarks to hadrons. The relics, in the form of quark nuggets expected to consist
of Strange Quark Matter, with a baryon number beyond a critical value will
survive. It is conjectured that color confinement turns the physical vacuum to
an event horizon for quarks and gluons. The horizon can be crossed only by
quantum tunnelling. The process just mentioned is the QCD counterpart of
Hawking radiation from gravitational black holes. Thus, when the Hawking
temperature of the quark nuggets gets turned off, tunnelling will stop and the
nuggets will survive forever. The baryon number and the mass of these nuggets
are derived using this theoretical format. The results agree well with the
prediction using other phenomenological models. Further, the variation of
Hawking temperature as a function of baryon number and mass of the nugget
mimicks chiral phase transition, somewhat similar to the QCD phase transition
just described. Finally the strange quark nuggets may well be the candidates of
baryonic dark matter.
