Monte Carlo simulations of the 3+1 dimensional NJL model are performed with baryon chemical potential μ > 0. For μ ∼ Σ0, the constituent quark mass in vacuum, chiral symmetry is restored and a diquark condensate 〈qq+〉 forms. We analyse the fermion propagator and find evidence for particle-hole mixing in the vicinity of the Fermi surface and an energy gap ∆ > 0, both of which provide evidence fo...

The 1/Nc expansion of QCD provides a valuable semiquantitative tool to study baryon scattering amplitudes and the short-lived baryon resonances embedded within them. A generalization of methods originally applied in chiral soliton models in the 1980’s provides the key to deriving a rigorous 1/Nc expansion. One obtains model-independent relations among amplitudes that impose mass and width degen...

The flavor-singlet H dibaryon, which has strangeness -2 and baryon number 2, is studied by the approach recently developed for the baryon-baryon interactions in lattice QCD. The flavor-singlet central potential is derived from the spatial and imaginary-time dependence of the Nambu-Bethe-Salpeter wave function measured in N(f)=3 full QCD simulations with the lattice size of L≃2,3,4  fm. The pote...

We consider a setup where R-parity is violated in the framework of split supersymmetry. The out-of-equilibrium decays of heavy squarks successfully lead to the generation of a baryon asymmetry. We restrict the R-parity violating couplings to the baryon number violating subset to keep the neutralino sufficiently stable to provide the dark matter. The observed baryon asymmetry can be generated fo...

For neutron stars with hyperon-mixed core, neutrino emissivity is studied under the equation of state, obtained by introducing three-body force universal for all baryons so as to assure the maximum mass compatible with the observation. By paying attention to the density dependence of the critical temperatures of the baryon superfluids, which reflect the nature of baryon-baryon interaction and c...

The similarity of the observed mass densities of baryons and cold dark matter may be a sign they have a related origin. The baryon-to-dark matter ratio can be understood in the MSSM with right-handed (RH) neutrinos if CDM is due to a d = 4 flat direction condensate of very weakly coupled RH sneutrino LSPs and the baryon asymmetry is generated by Affleck-Dine leptogenesis along a d = 4 (HuL) 2 f...

The mass spectra of nucleon resonances with spin 1 2 , 3 2 , and 5 2 are systematically studied in the constituent quark model with meson-quark coupling, which is inspired by the spontaneous breaking of chiral symmetry of QCD. The meson-quark coupling gives rise not only to the one-meson-exchange potential between quarks but also to the self-energy of baryon resonances due to the existence of m...

An attempt is made to study the symmetry properties of the strong baryon-meson couplingswithout using arguments concerning the origin of the baryon mass differences. It is shown that too high a symmetry is incompatible with associated production experiments. The argument is independent of perturbation theory. It is assumed that the Z and h have the same spin, that the (Z,h.) parity is even, and...

The chiral Lagrangian for baryons is formulated in an expansion in 1/Nc. The chiral Lagrangian implements the contracted spin-flavor symmetry of large-Nc baryons as well as nonet symmetry of the leading planar diagrams. Large-Nc consistency conditions ensure that chiral loop corrections are suppressed in 1/Nc through exact cancellation of chiral loop graphs to fixed orders in 1/Nc. Application ...