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arXiv · 1512.01317

Einstein-singleton theory and its power spectra in de Sitter inflation

Yun Soo Myung·Taeyoon Moon·Young-Jai Park
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Abstract

We study the Einstein-singleton theory during de Sitter inflation since it provides a way of degenerate fourth-order scalar theory. We obtain an exact solution expressed in terms of the exponential-integral function by solving the degenerate fourth-order scalar equation in de Sitter spacetime. Furthermore, we find that its power spectrum blows negatively up in the superhorizon limit, while it is negatively scale-invariant in the subhorizon limit. This suggests that the Einstein-singleton theory contains the ghost-instability and thus, it is not suitable for developing a slow-roll inflation model.

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Yun Soo Myung, Taeyoon Moon, Young-Jai Park. 2016-06-02. Einstein-singleton theory and its power spectra in de Sitter inflation. https://doi.org/10.1142/s0218271816501078

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