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arXiv · 1912.10830

Multi-pole Dark Energy

Abstract

While a scalar field with a pole in its kinetic term is often used to study the cosmological inflation, it can also play the role of dark energy, which is called the pole dark energy model. We propose a generalized model that the scalar field may have two or even multiple poles in the kinetic term and we call it the multi-pole dark energy. We find the poles can place some restrictions on the values of the original scalar field with non-canonical kinetic term. After transforming to the canonical form, we get a flat potential for the transformed new scalar field even if the original field has a steep one. It The late-time evolution of the universe is obtained explicitly for the two pole model, while dynamical analysis is performed for the multiple pole model. We find that it does have a stable attractor solution, which corresponds to the universe dominated by the potential of the scalar field.

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Chao-Jun Feng, Xiang-Hua Zhai, Xin-Zhou Li. 2019-12-19. Multi-pole Dark Energy. https://doi.org/10.1088/1674-1137%2Faba5f9

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