Massive states as the relevant deformations of gravitating branes

TL;DR

This paper explores how gravitating branes in five-dimensional theories lead to massive states and new IR scales, altering the effective dynamics of brane fluctuations and revealing scalar bound states with masses influenced by brane width.

Contribution

It introduces an exactly solvable model demonstrating the emergence of massive states and new IR scales due to gravity-induced symmetry breaking in brane theories.

Findings

Massive scalar bound states depend on brane width and are heavier than expected.

Spontaneous breaking of local translational invariance triggers a Higgs mechanism.

Explicit propagator expressions for the massive states are derived.

Abstract

Five-dimensional theories manifesting spontaneous brane generation are discussed in a gravitational context. Without gravity, the IR dynamics of the brane fluctuation below the brane tension scale is described by an effective theory for the Nambu-Goldstone modes. When gravity is properly taken into account the long distance dynamics changes. The spontaneous breaking of local translational invariance triggers the formation of massive representations via the Higgs mechanism and induces the appearance of new mass scales in the IR. These scales can in principle depend on other fundamental parameters besides the brane tension and the Planck scale. In noncompact extra dimensions the massive states are found to be scalar bound states. We obtain explicit expressions for their propagator and show that their masses depend on the brane width and are thus much heavier than expected. We present an exactly solvable model which captures the main features of the gravitational system.