  We discuss how a scenario recently proposed for the morphing of macroscopic
gravitation into weak interactions at the attometer scale affects our current
understanding of high-energy density phenomena. We find that the Yukawa
couplings of the fundamental fermions are directly related to their event
horizons, setting an upper bound $y_f\leq \sqrt{2}$ for their observability
through gauge interactions. Particles with larger Yukawa couplings are not
precluded, but should interact only gravitationally, providing a natural
candidate for dark matter. Furthermore, the quantum vacuum contribution to the
cosmological constant is reduced by several orders of magnitude with respect to
the current estimates. The expected running of the Newtonian gravitational
constant could provide a viable alternative scenario to the inflationary stage
of the Universe.
