Non-standard compactifications with mass gaps and Newton's law

TL;DR

This paper explores five-dimensional supergravity models with branes, demonstrating a mass gap in the graviton spectrum and calculating Yukawa corrections to Newton's law that can meet experimental constraints.

Contribution

It introduces new compactification models with a mass gap in the graviton spectrum, ensuring a well-defined four-dimensional effective gravity.

Findings

Graviton spectrum exhibits a genuine mass gap or is discrete.

Explicit calculation of Yukawa-type corrections to Newton's law.

Model parameters can be tuned to satisfy experimental bounds.

Abstract

The four-dimensional Minkowski space-time is considered as a three-brane embedded in five dimensions, using solutions of five-dimensional supergravity. These backgrounds have a string theoretical interpretation in terms of D3-brane distributions. By studying linear fluctuations of the graviton we find a zero-mode representing the massless graviton in four-dimensional space-time. The novelty of our models is that the graviton spectrum has a genuine mass gap (independent of the position of the world-brane) above the zero-mode or it is discrete. Hence, an effective four-dimensional theory on a brane that includes the massless graviton mode is well defined. The gravitational force between point particles deviates from the Newton law by Yukawa-type corrections, which we compute explicitly. We show that the parameters of our solutions can be chosen such that these corrections lie within experimental bounds.