Документ взят из кэша поисковой машины. Адрес оригинального документа : http://www.mrao.cam.ac.uk/~anthony/latex/Goyal.ps Дата изменения: Wed Jun 21 18:59:12 2000 Дата индексирования: Tue Oct 2 02:15:19 2012 Кодировка: Поисковые слова: storm

Dynamical evolution of quark-hadron phase transition
through bubble nucleation in the early Universe
Ashok Goyal et al.
Department of Physics and Astrophysics, University of Delhi
It is believed that the Universe has passed through a sucession of
phase transitions during its evolution. The phase transition from
quark-gluon plasma to conned hadronic phase proceeds through
the nucleation of hadronic bubbles as the Universe cools below the
critical temperature Tc  100MeV around 10 50s after the Big
Bang. The expansion of the hadronic phase forces the deconned
quark phase into smaller and smaller regions till the density be-
comes large enough to provide counterbalancing pressure and the
matter trapped in this region may stabilize into quark nuggets.
The size and mass of these nuggets depend upon the formation
time which is determined by the degree of super cooling.
The quark nuggets formed in the small super cooling scenario
are in a hot environment around the critical temperature Tc and
are susceptible to evaporation and boiling. However in the large
super cooling scenario we have the interesting possibility of these
nuggets forming at a much lower temperature than Tc due to the
long duration of the transition and consequent expansion of the
Universe. In this paper we determine the dynamical behaviour
of the quark-hadron phase transition estimating the evolution of
the hadron fraction, temperature and nucleation rate during the
process. We also explore the possibility of nugget formation and
their survivability.
Co-author: Deepak Chandra
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