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arXiv · 1405.3056

Towards a realistic solution of the cosmological constant fine-tuning problem by Higgs inflation

Chao-Jun Feng·Xin-Zhou Li
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Abstract

Why the cosmological constant $Λ$ observed today is so much smaller than the Planck scale or why the universe is accelerating at present? This is so-called the cosmological constant fine-tuning problem. In this paper, we find that this problem is solved with the help of Higgs inflation by simply assuming a variable cosmological "constant" during the inflation epoch. In the meanwhile, it could predict a large tensor-to-scalar ratio $r\approx 0.20$ and a large running of spectral index $n'_s \approx -0.028$ with a red-tilt spectrum $n_s \approx 0.96$, as well as a big enough number of e-folds $N\approx 40$ that required to solve the problems in the Big Bang cosmology with the help of $Λ$.

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Chao-Jun Feng, Xin-Zhou Li. 2014-05-13. Towards a realistic solution of the cosmological constant fine-tuning problem by Higgs inflation. https://doi.org/10.1103/physrevd.90.103009

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