Sliding Naturalness: Cosmological Selection of the Weak Scale

Understand

We present a cosmological solution to the electroweak hierarchy problem.

• After discussing general features of cosmological approaches to naturalness, we extend the Standard Model with two light scalars very weakly coupled to the Higgs and present the mechanism, which we recently introduced in a companion paper to explain jointly the electroweak hierarchy and the strong-CP problem.
• In this work we show that this solution can be decoupled from the strong-CP problem and discuss its possible implementations and phenomenology.
• The mechanism works with any standard inflationary sector, it does not require weak-scale inflation or a large number of e-folds, and does not introduce ambiguities related to eternal inflation.