  We present a calculation of thick-wall Coleman-de-Luccia (CdL) bounces in the
Standard Model effective potential in a de Sitter background. The calculation
is performed including the effect of the bounce back-reaction on the metric,
which we compare with the case of a fixed de-Sitter background, and with
similar full-backreaction calculation in a model polynomial potential. The
results show that the Standard Model potential exhibits non-trivial behavior:
rather than a single CdL solution, there are multiple (non-oscillating) bounce
solutions which may contribute to the decay rate. All the extra solutions found
have higher actions than the largest amplitude solution, and thus would not
contribute significantly to the decay rate, but their existence demonstrates
that CdL solutions in the Standard Model potential are not unique, and the
existence of additional, lower action, solutions cannot be ruled out. This
suggests that a better understanding of the appearance and disappearance of CdL
solutions in de Sitter space is needed to fully understand the vacuum
instability issue in the Standard Model.
