State-of-the-Art Calculation of the Decay Rate of Electroweak Vacuum

in the Standard Model

MOROI Takeo

With the precise determination of the Higgs mass at the LHC, now it is known that the electroweak (EW) vacuum, on which we are living, is unstable if the standard model is valid up to a very high scale. Thus, the understanding of the decay rate of the EW vacuum is an important issue. I will discuss recent progresses in the calculation of the decay rate of the EW vacuum. In particular, I will explain how to take care of artificial divergences which show up when there exist zero-modes around the so-called bounce configuration. I will show the result of the state-of-the-art calculation of the decay rate.

Relaxation Dynamics and Naturalness

KAPLAN David E.

The hierarchy and cosmological constant problems are, and have been for decades, significant sources of inspiration and confusion in particle physics. I will present a new class of solutions to the hierarchy (fine-tuned Higgs mass) problem called the 'relaxion'. Then I will present a new ingredient in general relativity -- using vorticity -- that may finally lead to a viable (and perhaps testable) solution to the cosmological constant problem.