  Use of supergravity equations in astronomy and late-universe cosmology is
often criticized on three grounds: (i) phenomenological success usually depends
on the supergravity form for the scalar potential applying at the relevant
energies; (ii) the low-energy scalar potential is extremely sensitive to
quantum effects involving very massive particles and so is rarely
well-approximated by classical calculations of its form; and (iii) almost all
Standard Model particles count as massive for these purposes and none of these
are supersymmetric. Why should Standard Model loops preserve the low-energy
supergravity form even if supersymmetry is valid at energies well above the
electroweak scale? We use recently developed tools for coupling supergravity to
non-supersymmetric matter to estimate the loop effects of heavy
non-supersymmetric particles on the low-energy effective action, and provide
evidence that the supergravity form is stable against integrating out such
particles (and so argues against the above objection). This suggests an
intrinsically supersymmetric picture of Nature where supersymmetry survives to
low energies within the gravity sector but not the visible sector (for which
supersymmetry is instead non-linearly realized). We explore the couplings of
both sectors in this picture and find that the presence of auxiliary fields in
the gravity sector makes the visible sector share many features usually
attributed to linearly realized supersymmetry although (unlike for the MSSM) a
second Higgs doublet is not required for all Yukawa couplings to be
non-vanishing and changes the dimension of the operator generating the Higgs
mass. We discuss the naturalness of this picture and some of the implications
it might have when searching for dark-sector physics.
