  Understanding the dynamic process of black hole thermodynamic phase
transitions at a triple point is a huge challenge. In this letter, we carry out
the first investigation of dynamical phase behaviour at a black hole triple
point. By numerically solving the Smoluchowski equation near the triple point
for a six-dimensional charged Gauss-Bonnet anti-de Sitter black hole, we find
that initial small, intermediate, or large black holes can transit to the other
two coexistent phases at the triple point, indicating that thermodynamic phase
transitions can indeed occur dynamically. More significantly, we observe
characteristic weak and strong oscillatory behaviour in this dynamic process,
which can be understood from an investigation of the rate of first passage from
one phase to another. Our results further an understanding of the dynamic
process of black hole thermodynamic phase transitions.
