  A comparison is made of a range of proposals to include free and bound black
holes as either a small component or the dominant constituent of dark matter.
The hypothesis that dark matter consists of atomic gravitationally bound
primordial black holes is closely examined in 3-space, as well as in n-space.
It is demonstrated that for dimensions greater than 3, stable gravitational or
electrostatic atoms cannot be bound by energy constraints. The total number of
degrees of freedom of a d-dimensional body in n-space is derived so that
equipartition of energy may be applied in the early universe. Blackbody and
Hawking radiation are generalized to n-space. A promising new approach to black
hole entropy is presented.
