A String and M-theory Origin for the Salam-Sezgin Model

TL;DR

This paper derives a string and M-theory foundation for the Salam-Sezgin supergravity model by embedding it into higher-dimensional supergravity theories through consistent reductions, linking it to brane geometries.

Contribution

It provides the first explicit embedding of the Salam-Sezgin model into string/M-theory via a consistent Pauli reduction on a hyperboloid, extending understanding of its higher-dimensional origin.

Findings

Embedded Salam-Sezgin model in type I and heterotic supergravity.

Connected the model's ground state to NS5-brane near-horizon geometry.

Demonstrated embeddings of larger gauged supergravities in six dimensions.

Abstract

An M/string-theory origin for the six-dimensional Salam-Sezgin chiral gauged supergravity is obtained, by embedding it as a consistent Pauli-type reduction of type I or heterotic supergravity on the non-compact hyperboloid ${\cal H}^{2,2}$ times $S^1$. We can also obtain embeddings of larger, non-chiral, gauged supergravities in six dimensions, whose consistent truncation yields the Salam-Sezgin theory. The lift of the Salam-Sezgin (Minkowski)$_4\times S^2$ ground state to ten dimensions is asymptotic at large distances to the near-horizon geometry of the NS5-brane.