[Seminar] "Vacuum decay rate in the standard model and beyond" by Dr. Yutaro Shoji

Quantum Gravity Unit (Neiman Unit) would like to invite you to a seminar by Dr. Yutaro Shoji from Nagoya University

Title: "Vacuum decay rate in the standard model and beyond"

Abstract:
The electroweak vacuum is not absolutely stable in the standard model and various models beyond the standard model. This is due to an appearance of another deeper vacuum, into which the electroweak vacuum can decay. The decay proceeds through quantum tunneling and the rate is expressed with an exponential suppression factor and a pre-factor. The suppression factor has been calculated in many papers, but a naive dimensional analysis has been usually adopted for the pre-factor.

We have pointed out that such an evaluation can suffer from large quantum corrections and it is important to calculate the pre-factor as well.

To calculate the pre-factor, we had problems in a gauge sector; its gauge invariance is not explicitly shown, and there appear zero modes, which we could not deal with.

We have solved these problems and made it possible to determine vacuum decay rates precisely.

As applications, we analyzed the decay rates in the standard model and its fermionic extensions. We also provide a public code, which can be used for models that exhibit classical scale invariance at a high energy scale.