Planckian Interacting Massive Particles as Dark Matter
  The Standard Model could be self-consistent up to the Planck scale according
to the present measurements of the Higgs mass and top quark Yukawa coupling. It
is therefore possible that new physics is only coupled to the Standard Model
through Planck suppressed higher dimensional operators. In this case the WIMP
miracle is a mirage, and instead minimality as dictated by Occam's razor would
indicate that dark matter is related to the Planck scale, where quantum gravity
is anyway expected to manifest itself. Assuming within this framework that dark
matter is a Planckian Interacting Massive Particle, we show that the most
natural mass larger than $0.01\,\textrm{M}_p$ is already ruled out by the
absence of tensor modes in the CMB. This also indicates that we expect tensor
modes in the CMB to be observed soon for this type of minimal dark matter
model. Finally, we touch upon the KK graviton mode as a possible realization of
this scenario within UV complete models, as well as further potential
signatures and peculiar properties of this type of dark matter candidate. This
paradigm therefore leads to a subtle connection between quantum gravity, the
physics of primordial inflation, and the nature of dark matter.
