Microscopic completion and radiative stability of the constrained supergravity construction

Establish the microscopic origin of the nilpotent multiplet, determine the associated fermionic and gravitino dynamics, and prove the radiative stability of the tree-level constrained-supergravity effective field theory used to realize quantum selection of classical histories.

Background

The paper realizes transient quantum access to multiple pre-existing classical inflationary continuations using a tree-level bosonic scalar effective field theory embedded in constrained mathcal N=1 supergravity with a nilpotent goldstino multiplet. The construction specifies the bosonic Kähler potential, superpotential, branch-selector profile, coupled scalar perturbations, and mode-derived stochastic dynamics, but does not provide a microscopic ultraviolet origin for the nilpotent multiplet.

The authors also leave the fermionic and gravitino sectors untreated and do not establish that the proposed constrained-supergravity realization remains stable under radiative corrections. Resolving these issues would be necessary to determine whether the mechanism persists in a more complete supergravity or ultraviolet framework rather than only within the stated tree-level bosonic effective description.