  We study negative modes around the Coleman-de Luccia bounce solution. The
conditions for the appearance of an infinite number of the negative modes do
not coincide between Lagrangian and Hamiltonian formulations in the literature,
and we discuss the origin of this difference in detail. We show how different
choices of the variable for the fluctuation around the bounce solution affect
the negative mode condition in the Hamiltonian approach, and point out that
there exists a choice which gives the same negative mode condition as the
Lagrangian approach.
