Semiclassical geons as solitonic black hole remnants
  We find that the end state of black hole evaporation could be represented by
non-singular and without event horizon stable solitonic remnants with masses of
the order the Planck scale and up to 16 units of charge. Though these objects
are locally indistinguishable from spherically symmetric, massive electric (or
magnetic) charges, they turn out to be sourceless geons containing a wormhole
generated by the electromagnetic field. Our results are obtained by
interpreting semiclassical corrections to Einstein's theory in the first-order
(Palatini) formalism, which yields second-order equations and avoids the
instabilities of the usual (metric) formulation of quadratic gravity. We also
discuss the potential relevance of these solutions for primordial black holes
and the dark matter problem.
