DBI from Gravity

TL;DR

This paper investigates gravitational lumps in string theory, analyzing how broken symmetries constrain localized modes, and demonstrates a critical electric field value in a Taub-NUT background derived from gravity alone.

Contribution

It introduces a gravitational perspective on symmetry constraints for localized modes in gravitational lumps, extending brane physics analogies without relying on higher derivative terms.

Findings

Broken symmetries constrain localized modes.

Critical electric field arises from gravity in Taub-NUT background.

Constraints are gravitational analogues of brane physics results.

Abstract

We study the dynamics of gravitational lumps. By a lump, we mean a metric configuration that asymptotes to a flat space-time. Such lumps emerge in string theory as strong coupling descriptions of D-branes. We provide a physical argument that the broken global symmetries of such a background, generated by certain large diffeomorphisms, constrain the dynamics of localized modes. These modes include the translation zero modes and any localized tensor modes. The constraints we find are gravitational analogues of those found in brane physics. For the example of a Taub-NUT metric in eleven-dimensional supergravity, we argue that a critical value for the electric field arises from standard gravity without higher derivative interactions.