Rates for nucleation of two-flavor quark matter in a neutron star core, originally composed of nuclear matter in β equilibrium, are calculated at zero temperature by a quantum tunneling analysis incorporating the electrostatic energy. We find that a nucleated droplet would develop into bulk matter due to electron screening effects. ∗) E-mail address: [email protected] ∗∗) E-mail...

We present a new scenario for the development of the Universe after the Big Bang, built on the conjecture that a vast majority of the primordial quark matter did not undergo a phase transition to normal nuclear matter, but rather split up into massive quark objects that remained stable. Hence, such primordial quark matter would make up the so-called dark matter. We discuss, mostly in qualitativ...

At greater than nuclear densities, matter may convert into a mixture of nucleons, hyperons, dibaryons, and strangelets, thus facilitating the formation of strange matter even before the onset of the quark-matter phase transition. From a nonstrange dibaryon condensate, it may even be possible to leapfrog into strange matter with a certain new interaction, represented by an effective six-quark op...

We have constructed equations of state involving various exotic forms of matter with large strangeness fraction such as hyperon matter, Bose-Einstein condensates of antikaons and strange quark matter. First order phase transitions from hadronic to antikaon condensed and quark matter are considered here. The hadronic phase is described by the relativistic field theoretical model. Later those equ...

For physically reasonable bulk and surface properties, quark matter has recently been found to coexist with nuclear matter inside neutron stars in a uniform background of electrons. The microstructure of this mixed phase starts out with a few quark matter droplets embedded in the nuclear matter but as the density of droplets increase towards the center of the neutron star they merge into rods, ...

By colliding ultrarelativistic ions, one achieves presently energy densities close to the critical value, concerning the formation of a quark-gluon-plasma. This indicates the importance of fluctuations and the necessity to go beyond the investigation of average events. Therefore, we introduce a percolation approach to model the final stage (τ > 1 fm/c) of ion-ion collisions, the initial stage b...

Effects of energy dissipation on quantum nucleation of two-flavor quark matter in dense nuclear matter encountered in neutron star cores are examined at low temperatures. We find that low-energy excitations of nucleons and electrons reduce the nucleation rate exponentially via their collisions with the surface of a quark matter droplet. ∗) E-mail address: [email protected] 1 typ...

We construct the nuclear and quark matter equations of state at zero temperature in an effective quark theory (the Nambu-JonaLasinio model), and discuss the phase transition between them. The nuclear matter equation of state is based on the quark-diquark description of the single nucleon, while the quark matter equation of state includes the effects of scalar diquark condensation (color superco...