Stainless super p-branes

TL;DR

This work expands the landscape of supersymmetric p-brane solutions by introducing the notion of stainless branes—solutions that cannot be isotropically oxidized to higher dimensions—thereby revealing new stainless families in $5\le D\le 9$, including a 6-brane and a 5-brane in $D=9$, a string in $D=5$, and particles in several dimensions. By systematically applying Kaluza-Klein reduction and analyzing dilaton couplings through the parameter $\Delta$ and the coefficient $a$, the authors show how some lower-dimensional branes descend from known higher-dimensional branes while others lie beyond oxidation, necessitating a stainless/br rusty dichotomy to complete the brane scan. They provide explicit Lagrangians, solution ansätze, and supersymmetry checks for these stainless branes, including new $D=9$ examples and the associated zero-mode structures, illustrating how half-BPS conditions are realized in diverse dimensional settings. The results refine the brane-scanning program and reveal the nuanced role of isotropic oxidation, dilaton couplings, and KK reductions in shaping the full spectrum of supersymmetric p-branes, with implications for worldvolume theories and the global structure of supergravity theories across dimensions.

Abstract

The elementary and solitonic supersymmetric $p$-brane solutions to supergravity theories form families related by dimensional reduction, each headed by a maximal (`stainless') member that cannot be isotropically dimensionally oxidized into higher dimensions. We find several new families, headed by stainless solutions in various dimensions $D\le 9$. In some cases, these occur with dimensions $(D,p)$ that coincide with those of descendants of known families, but since the new solutions are stainless, they are necessarily distinct. The new stainless supersymmetric solutions include a 6-brane and a 5-brane in $D=9$, a string in $D=5$, and particles in all dimensions $5\le D\le 9$.