The Gravitino Swampland Conjecture

TL;DR

This paper proposes the Gravitino Swampland Conjecture, asserting that the gravitino's sound speed cannot vanish in EFTs compatible with quantum supergravity, impacting string theory models and observational prospects.

Contribution

It introduces a new swampland criterion related to the gravitino's properties, extending the landscape of inconsistent EFTs to include those incompatible with quantum supergravity.

Findings

Supports the conjecture with KKLT and LVS string theory scenarios

Implications for quantum supergravity consistency conditions

Potential observational consequences of the gravitino sound speed constraint

Abstract

We extend the swampland from effective field theories (EFTs) inconsistent with quantum gravity to EFTs inconsistent with quantum supergravity. This enlarges the swampland to include EFTs that become inconsistent when the gravitino is quantized. We propose the Gravitino Swampland Conjecture: the gravitino sound speed must be non-vanishing in all EFTs that are low energy limits of quantum supergravity. This seemingly simple statement has important consequences for both theories and observations. The conjecture is consistent with and supported by the KKLT and LVS scenarios for moduli stabilization in string theory.