Three-forms and Fayet-Iliopoulos terms in Supergravity: Scanning Planck mass and BPS domain walls

Understand

We embed a new three-form vector multiplet in ${\cal N}=1$ supergravity and we show that it can be used to generate dynamically the Hilbert--Einstein term.

• We then recast the theory into the standard Freedman model and we argue that a pure Fayet--Iliopoulos term is in tension with the weak gravity conjecture.
• Finally, we couple the three-form to a super-membrane and study BPS domain walls within matter-coupled supergravity.
• In these models, the Planck mass takes different values on the domain wall sides.