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arXiv · 2405.06921

Perturbations of Mimetic Curvaton

Anxianyi Xiong·Xin-zhe Zhang·Taotao Qiu
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Abstract

The mimetic gravity theory is one of the interesting modified gravity theories, which aims to unify the matter component of our universe within the power of gravity. The mimetic-like theory can also be responsible for primordial perturbations production, e.g., when the mimetic field is set to be like a curvaton field, and the adiabatic perturbation can thus be generated from the isocurvature perturbation via usual curvaton mechanism [1]. In the original mimetic curvaton model, the parameter $\lambda$ was purely an algebraic multiplier, lack of any perturbed dynamics. In the current paper, we treat $\lambda$ as an auxiliary field, with its perturbation $\delta\lambda$ evolving alongside. We show that, with such a consideration, the adiabatic perturbation can still be generated from the curvaton mechanism, and becomes scale invariant with different field space configurations.

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Anxianyi Xiong, Xin-zhe Zhang, Taotao Qiu. 2024-05-11. Perturbations of Mimetic Curvaton. https://arxiv.org/abs/2405.06921

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