In the context of type-IIA orientifold compactifications,we discuss the fermion masses in a two-singlet-extended minimal-supersymmetric-standard-model four-stack quiver with U(3)×Sp(1)×U(1)×U(1)gauge sy...In the context of type-IIA orientifold compactifications,we discuss the fermion masses in a two-singlet-extended minimal-supersymmetric-standard-model four-stack quiver with U(3)×Sp(1)×U(1)×U(1)gauge symmetry.The corresponding effective superpotential exhibits hierarchical coupling term scales giving a partial solution to the fermion masses problem.Using the known data with upper bound neutrino masses mvt≤2 eV,we estimate the relevant scales for the model.展开更多
Using N=2 supergravity formalism,we investigate certain behaviors of five-dimensional black objects from the compactification of M-theory on a Calabi-Yau three-fold.The manifold has been constructed as the intersectio...Using N=2 supergravity formalism,we investigate certain behaviors of five-dimensional black objects from the compactification of M-theory on a Calabi-Yau three-fold.The manifold has been constructed as the intersection of two homogeneous polynomials of degrees(ω+2,1)and(2,1)in a product of two weighted projective spaces given by WP^(4)(ω,1,1,1,1)×P^(1).First,we determine the allowed electric charge regions of the BPS and non BPS black holes obtained by wrapping M2-branes on appropriate two cycles in such a proposed Calabi-Yau three-fold.After that,we calculate the entropy of these solutions which takes a maximal value corresponding to ω=1 defining the ordinary projective space P^(4).For generic values of ω,we show that the non BPS states are unstable.Then,we conduct a similar study of five-dimensional black strings.Concerning the allowed magnetic charge regions of the BPS and non BPS black stringy solutions derived from M5-branes on dual divisors,we calculate the tension taking a minimal value for P^(4).By determining the recombination factor,we show that the non-BPS black string states are stable in the allowed regions in the magnetic charge space.展开更多
The recent observation of higher quark combinations, tetraquarks and pentaquarks, is a strong indication of more exotic hadrons. Using Z_2 and Z_3 symmetries and standard model data, a general quark combination produc...The recent observation of higher quark combinations, tetraquarks and pentaquarks, is a strong indication of more exotic hadrons. Using Z_2 and Z_3 symmetries and standard model data, a general quark combination producing new hadronic states is proposed in terms of polygon geometries according to the Dynkin diagrams of ?_n affine Lie algebras. It has been shown that Z_(2,3) invariance is crucial in the determination of the mesonic or the baryonic nature of these states. The hexagonal geometry is considered in some details producing both mesonic and baryonic states. A general class of this family is also presented.展开更多
文摘In the context of type-IIA orientifold compactifications,we discuss the fermion masses in a two-singlet-extended minimal-supersymmetric-standard-model four-stack quiver with U(3)×Sp(1)×U(1)×U(1)gauge symmetry.The corresponding effective superpotential exhibits hierarchical coupling term scales giving a partial solution to the fermion masses problem.Using the known data with upper bound neutrino masses mvt≤2 eV,we estimate the relevant scales for the model.
文摘Using N=2 supergravity formalism,we investigate certain behaviors of five-dimensional black objects from the compactification of M-theory on a Calabi-Yau three-fold.The manifold has been constructed as the intersection of two homogeneous polynomials of degrees(ω+2,1)and(2,1)in a product of two weighted projective spaces given by WP^(4)(ω,1,1,1,1)×P^(1).First,we determine the allowed electric charge regions of the BPS and non BPS black holes obtained by wrapping M2-branes on appropriate two cycles in such a proposed Calabi-Yau three-fold.After that,we calculate the entropy of these solutions which takes a maximal value corresponding to ω=1 defining the ordinary projective space P^(4).For generic values of ω,we show that the non BPS states are unstable.Then,we conduct a similar study of five-dimensional black strings.Concerning the allowed magnetic charge regions of the BPS and non BPS black stringy solutions derived from M5-branes on dual divisors,we calculate the tension taking a minimal value for P^(4).By determining the recombination factor,we show that the non-BPS black string states are stable in the allowed regions in the magnetic charge space.
文摘The recent observation of higher quark combinations, tetraquarks and pentaquarks, is a strong indication of more exotic hadrons. Using Z_2 and Z_3 symmetries and standard model data, a general quark combination producing new hadronic states is proposed in terms of polygon geometries according to the Dynkin diagrams of ?_n affine Lie algebras. It has been shown that Z_(2,3) invariance is crucial in the determination of the mesonic or the baryonic nature of these states. The hexagonal geometry is considered in some details producing both mesonic and baryonic states. A general class of this family is also presented.
