Black holes and the Higgs vacuum

Under certain conditions the universe can undergo a phase transition by tunneling from a "false vacuum". This process of vacuum decay is well captured by a classical solution in Euclidean time - the instanton, first found by Coleman and de Luccia. This process is now a "gold standard" for describing any sort of tunneling decay involving gravity, however, just as impurities can act as nucleation sites in a phase transition, I will explain how gravitational impurities, in the guise of black holes, can also act as nucleation sites for decay, and how the probability of vacuum decay is enhanced. I will also discuss implications for the stability of the Higgs vacuum.