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arXiv · hep-th/0304048

Cosmological Scaling Solutions and Multiple Exponential Potentials

Zong-Kuan Guo·Yun-Song Piao·Yuan-Zhong Zhang
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Abstract

We present a phase-space analysis of cosmology containing multiple scalar fields with positive and negative exponential potentials. We show that there exist power-law multi-kinetic-potential scaling solutions for sufficiently flat positive potentials or steep negative potentials. The former is the unique late-time attractor and the well-known assisted inflationary solution, but the later is never unstable in an expanding universe. Moreover, for steep negative potentials there exist a kinetic-dominated regime in which each solution is a late-time attractor. We briefly discuss the physical consequences of these results.

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Zong-Kuan Guo, Yun-Song Piao, Yuan-Zhong Zhang. 2003-06-17. Cosmological Scaling Solutions and Multiple Exponential Potentials. https://doi.org/10.1016/j.physletb.2003.06.004

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