  As a follow up of the seminal work by Guiot, Borquez, Deur, and Werner on
"Graviballs and Dark Matter", we explicitly show that contrary to Einstein's
gravity, in string theory, local and nonlocal higher derivative theories, as
well as general asymptotically-free or finite theories, gravitationally
interacting bound states can form when the energy is larger than the Planck
energy. On the other hand, in higher derivative or nonlocal theories with
interaction governed by a dimensionless or a dimensionful coupling constant,
the bound states form when the energy is smaller than the Planck energy. Such
bound states are allowed because of the softness of the scattering amplitudes
in the ultraviolet region. Indeed, in such theories, the potential is finite
while the force is zero or constant in $r=0$. Finally, since the bound states
that form in the early Universe may have an energy that ranges from the Planck
mass to any arbitrarily large or small value, we argue that they can serve as
dark matter candidates and/or as the seeds for the structure's formation at
large scale in the Cosmos.
