We have derived a set of field equations for a Weyssenhoff spin fluid including magnetic interaction among the spinning particles prevailing in spatially homogeneous, but anisotropically cosmological models of Bianchi...We have derived a set of field equations for a Weyssenhoff spin fluid including magnetic interaction among the spinning particles prevailing in spatially homogeneous, but anisotropically cosmological models of Bianchi type V based on Einstein Cartan theory. We analyze the field equations in three different equations of states specified by p =(1/3)ρ, p =ρ and p =0. The analytical solutions found are non singular provided that the combined energy arising from matter spin and magnetic interaction among particles overcomes the anisotropy energy in the Universe. We have also deduced that the minimum particle numbers for the radiation ( p =(1/3)ρ ) and matter ( p =0) epochs are 10 88 and 10 108 respectively, the minimum particle number for the state p =ρ is 10 96 , leading to the conclusion that we must consider the existence of neutrinos and other creation of particles and anti particles under torsion and strong gravitational field in the early Universe.展开更多
In this article we extend the notion of constant angle surfaces in S2 × R and H2 ×R to general Bianchi-Cartan-Vranceanu spaces. We show that these surfaces have constant Gaussian curvature and we give a comp...In this article we extend the notion of constant angle surfaces in S2 × R and H2 ×R to general Bianchi-Cartan-Vranceanu spaces. We show that these surfaces have constant Gaussian curvature and we give a complete local classification in the Heisenberg group.展开更多
文摘We have derived a set of field equations for a Weyssenhoff spin fluid including magnetic interaction among the spinning particles prevailing in spatially homogeneous, but anisotropically cosmological models of Bianchi type V based on Einstein Cartan theory. We analyze the field equations in three different equations of states specified by p =(1/3)ρ, p =ρ and p =0. The analytical solutions found are non singular provided that the combined energy arising from matter spin and magnetic interaction among particles overcomes the anisotropy energy in the Universe. We have also deduced that the minimum particle numbers for the radiation ( p =(1/3)ρ ) and matter ( p =0) epochs are 10 88 and 10 108 respectively, the minimum particle number for the state p =ρ is 10 96 , leading to the conclusion that we must consider the existence of neutrinos and other creation of particles and anti particles under torsion and strong gravitational field in the early Universe.
文摘In this article we extend the notion of constant angle surfaces in S2 × R and H2 ×R to general Bianchi-Cartan-Vranceanu spaces. We show that these surfaces have constant Gaussian curvature and we give a complete local classification in the Heisenberg group.