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arXiv · 2107.14115

Anisotropic constant-roll inflation for the Dirac-Born-Infeld model

Duy H. Nguyen·Tuyen M. Pham·Tuan Q. Do
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Abstract

In this paper, we study a non-canonical extension of a supergravity-motivated model acting as a vivid counterexample to the cosmic no-hair conjecture due to its unusual coupling between scalar and electromagnetic fields. In particular, a canonical scalar field is replaced by the string-inspired Dirac-Born-Infeld one in this extension. As a result, exact anisotropic inflationary solutions for this Dirac-Born-Infeld model are figured out under a constant-roll condition. Furthermore, numerical calculations are performed to verify that these anisotropic constant-roll solutions are indeed attractive during their inflationary phase.

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Duy H. Nguyen, Tuyen M. Pham, Tuan Q. Do. 2021-07-29. Anisotropic constant-roll inflation for the Dirac-Born-Infeld model. https://doi.org/10.1140/epjc%2Fs10052-021-09652-1

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