Naturally-Coupled Dark Sectors
  The dark sector, composed of the fields neutral under the Standard Model (SM)
gauge group, can couple to the SM through the Higgs, hypercharge and neutrino
portals, and pull the SM towards its scale by loop corrections. This
instability, not possible to prevent in the known SM completions like
supersymmetry due to their sizable couplings to the SM, calls for alternative
mechanisms which can neutralize sensitivities of the SM to the dark sector
scale and to the ultraviolet cutoff above it. Here we review such a mechanism
in which incorporation of gravity into the SM predicts the existence of a dark
sector and allows it to be naturally-coupled to the SM. We discuss and
illustrate salient processes which can probe the naturally-coupled dark
sectors.
