Metastable Electroweak Vacuum: Implications for Inflation

Understand

Within the Standard Model, the current Higgs and top quark data favor metastability of the electroweak vacuum, although the uncertainties are still significant.

• The true vacuum is many orders of magnitude deeper than ours and the barrier separating the two is tiny compared to the depth of the well.
• This raises a cosmological question: how did the Higgs field get trapped in the shallow minimum and why did it stay there during inflation? The Higgs initial conditions before inflation must be fine--tuned to about one part in 10^8 in order for the Higgs field to end up in the right vacuum.
• In this note, we show that these problems can be resolved if there is a small positive coupling between the Higgs and the inflaton.