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arXiv · 2401.00352

Constant-roll inflation with tachyon field in the holographic braneworld

Marko Stojanovic·Neven Bilic·Dragoljub D. Dimitrijevic·Goran S. Djordjevic·Milan Milosevic
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Abstract

We study inflation driven by the tachyon field in the holographic braneworld by assuming the second slow-roll parameter $\eta$ is constant. The parameter $\eta$ can be either defined by the tachyon scalar field and the Hubble parameter or by the Hubble parameter only. By assuming a constant $\eta$, we derive and numerically solve a differential equation for the Hubble expansion rate. We calculate numerically the scalar spectral index and the tensor-to-scalar ratio. We confront the results with the observational data and find some constraints on the free model parameters. The swampland conjectures are discussed in the context of the constant-roll inflation, with some accent on the holographic model.

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Marko Stojanovic, Neven Bilic, Dragoljub D. Dimitrijevic, Goran S. Djordjevic, Milan Milosevic. 2023-12-30. Constant-roll inflation with tachyon field in the holographic braneworld. https://doi.org/10.1088/1361-6382/ad6058

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