中国物理B ›› 2013, Vol. 22 ›› Issue (5): 59801-059801.doi: 10.1088/1674-1056/22/5/059801
• GEOPHYSICS, ASTRONOMY, AND ASTROPHYSICS • 上一篇
张开源, 吴普训, 余洪伟
Zhang Kai-Yuan (张开源), Wu Pu-Xun (吴普训), Yu Hong-Wei (余洪伟)
摘要: We analyze the attractor behaviour of the inflation field in braneworld scenarios using the Hamilton-Jacobi formalism, where the Friedmann equation has the form of H2=ρ+ε√2ρ0ρ or H2=ρ+ερ2/2σ, with ε=±1. We find that in all models the linear homogeneous perturbation can decay exponentially as the scalar field rolls down its potential. However, in the case of a -ρ2 correction to the standard cosmology with ρ < σ, the existence of an attractor solution requires (σ-ρ)/φ2 > 1. Our results show that the perturbation decays more quickly in models with positive-energy correction than in the standard cosmology, which is opposite to the case of negative-energy correction. Thus, the positive-energy modification rather than the negative one can assist the inflation and widen the range of initial conditions.
中图分类号: (Cosmology)