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arXiv · 1603.07572

Observational signatures of Higgs inflation

Vera-Maria Enckell·Kari Enqvist·Sami Nurmi
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Abstract

We investigate the dependency of Higgs inflation on the non-renormalisable matching between the low energy Standard Model limit and the inflationary regime at high energies. We show that for the top mass range $m_t \gtrsim 171.8$ GeV the scenario robustly predicts the spectral index $n_s \simeq 0.97$ and the tensor-to-scalar ratio $r\simeq 0.003$. The matching is however non-trivial, even the best-fit values $m_h=125.09$ GeV and $m_t=173.21$ GeV require a jump $δλ\sim 0.01$ in the Higgs coupling below the inflationary scale. For $m_t\lesssim 171.8$ GeV, the matching may generate a feature in the inflationary potential. In this case the predicted values of $n_s$ and $r$ vary but the model is still falsifiable. For example, a detection of negative running of spectral index at level $α_s \lesssim -0.01$ would rule out Higgs inflation.

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Vera-Maria Enckell, Kari Enqvist, Sami Nurmi. 2016-03-24. Observational signatures of Higgs inflation. https://doi.org/10.1088/1475-7516%2F2016%2F07%2F047

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