The Clayton Antitrust Act of 1914 prohibits corporate mergers that would
result in certain highly undesired end states. We study an exact solution of
the Einstein equations describing localized, charged Kaluza-Klein black holes
in a collapsing deSitter universe and seek to demonstrate that a similar effect
holds, preventing a potentially catastrophic black hole merger. As the collapse
proceeds, it is natural to expect that the black hole undergoes a topological
transition, wrapping around the shrinking compact dimension to merge with
itself and form a black string. However, the putative uniform charged black
string end state is singular and such a transition would violate (a reasonable
notion of) cosmic censorship. We present analytic and numerical evidence that
strongly suggests the absence of such a transition. Based on this evidence, we
expect that the Kaluza-Klein black hole horizon stays localized, despite the
increasingly constraining size of the compact dimension. On the other hand, the
deSitter horizon does change between spherical and cylindrical topologies in a
simple way.Comment: 25 pages, 6 figure
