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arXiv · 1810.04436

Perturbations of bounce inflation scenario from $f(T)$ modified gravity revisited

Taotao Qiu·Kun Tian·Shaojun Bu
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Abstract

In this work, we revisit the perturbations that are generated in the bounce inflation scenario constructed within the framework of $f(T)$ theory. It has been well known that pure $f(T)$ theory cannot give rise to bounce inflation behavior, so aside from the gravity part, we also employ a canonical scalar field for minimal extension. We calculate the perturbations in $f(T)$ theory using the well-established ADM formalism, and find various conditions to avoid their pathologies. We find that it is indeed very difficult to obtain a healthy model without those pathologies, however, one may find a way out if a potential requirement, say, to keep every function continuous, is abandoned.

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Taotao Qiu, Kun Tian, Shaojun Bu. 2018-10-10. Perturbations of bounce inflation scenario from $f(T)$ modified gravity revisited. https://doi.org/10.1140/epjc%2Fs10052-019-6782-8

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