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arXiv · 2304.08874

Anisotropic power-law inflation for a generalized model of two scalar and two vector fields

Tuan Q. Do·W. F. Kao
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Abstract

Cosmological implication of a generalized model of two scalar and two vector fields, in which both scalar fields are non-minimally coupled to each vector field, is studied in this paper. In particular, we will seek a set of new anisotropic power-law inflationary solutions to this model. Additionally, the stability of the obtained solutions will be examined by using the dynamical system approach. As a result, we will show that this set of solutions turns out to be stable and attractive during the inflationary phase as expected due to the existence of the unusual couplings between two scalar and two vector fields. Notably, we will point out that the existence of phantom field will lead to an instability of the corresponding anisotropic power-law inflation.

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Tuan Q. Do, W. F. Kao. 2023-04-18. Anisotropic power-law inflation for a generalized model of two scalar and two vector fields. https://doi.org/10.1088/1402-4896%2Fad0f82

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