  Any probe which crosses the horizon of a black hole should be absorbed. In
M(atrix) theory, for 0-brane probes of Schwarzschild black holes, we argue that
the relevant absorption mechanism is a tachyon instability which sets in at the
horizon. We give qualitative arguments, and some quantitative large-N
calculations, in support of this claim. The tachyon instability provides an
attractive mechanism for infalling matter to be captured and thermalized by a
Schwarzschild black hole.
