DE1 - Dark Energy and the Accelerating Universe |
Speaker |
Chiba, Takeshi |
Coauthors |
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Talk Title |
Reconstructing the Inflaton Potential from the Spectral Index |
Abstract |
The recent cosmological observations are in good agreement with the scalar spectral index $n_s$ with $n_s-1\sim -2/N$, where $N$ is the number of e-foldings. Quadratic chaotic model, Starobinsky model and Higgs inflation or $\alpha$-attractors connecting them are typical examples predicting such a relation. We consider the problem in the opposite: given $n_s$ as a function of $N$, what is the inflaton potential $V(\phi)$. We find that for $n_s-1=-2/N$, $V(\phi)$ is either $\tanh^2(\gamma\phi/2)$ ("T-model") or $\phi^2$ (chaotic inflation) to the leading order in the slow-roll approximation. We also derive formulas for $n_s-1=-p/N$. |
Talk view |
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