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arXiv · 1505.05955

Constrained inflaton due to a complex scalar

Romy H. S. Budhi·Shoichi Kashiwase·Daijiro Suematsu
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Abstract

We reexamine inflation due to a constrained inflaton in the model of a complex scalar. Inflaton evolves along a spiral-like valley of special scalar potential in the scalar field space just like single field inflation. Sub-Planckian inflaton can induce sufficient $e$-foldings because of a long slow-roll path. In a special limit, the scalar spectral index and the tensor-to-scalar ratio has equivalent expressions to the inflation with monomial potential $φ^n$. The favorable values for them could be obtained by varying parameters in the potential. This model could be embedded in a certain radiative neutrino mass model.

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Romy H. S. Budhi, Shoichi Kashiwase, Daijiro Suematsu. 2015-09-18. Constrained inflaton due to a complex scalar. https://doi.org/10.1088/1475-7516%2F2015%2F09%2F039

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