Massive Supergravity and Deconstruction

TL;DR

This paper introduces a superfield Lagrangian for massive supergravity, analyzing its properties, goldstone multiplets, and applications to deconstruction, revealing key interactions, mass scales, and quantum effects.

Contribution

It provides the first simple superfield Lagrangian for massive supergravity, generalizing Fierz-Pauli, and explores its implications for deconstruction and quantum effects.

Findings

Goldstone supermultiplet acquires kinetic term via mixing

Massive supergravity exhibits Planck scale interactions and unitarity bounds

Single multiplet can mimic extra dimension in anomaly mediation

Abstract

We present a simple superfield Lagrangian for massive supergravity. It comprises the minimal supergravity Lagrangian with interactions as well as mass terms for the metric superfield and the chiral compensator. This is the natural generalization of the Fierz-Pauli Lagrangian for massive gravity which comprises mass terms for the metric and its trace. We show that the on-shell bosonic and fermionic fields are degenerate and have the appropriate spins: 2, 3/2, 3/2 and 1. We then study this interacting Lagrangian using goldstone superfields. We find that a chiral multiplet of goldstones gets a kinetic term through mixing, just as the scalar goldstone does in the non-supersymmetric case. This produces Planck scale (Mpl) interactions with matter and all the discontinuities and unitarity bounds associated with massive gravity. In particular, the scale of strong coupling is (Mpl m^4)^1/5, where m is the multiplet's mass. Next, we consider applications of massive supergravity to deconstruction. We estimate various quantum effects which generate non-local operators in theory space. As an example, we show that the single massive supergravity multiplet in a 2-site model can serve the function of an extra dimension in anomaly mediation.