Massless 3-brane in M-theory

TL;DR

This paper constructs supersymmetric, massless M3-brane solutions in M-theory as deformations of Ricci-flat G_2 holonomy backgrounds, including M5-branes wrapped over S^2, expanding the landscape of known supergravity solutions.

Contribution

It introduces new massless M3-brane solutions in D=11 supergravity, highlighting their supersymmetry and relation to G_2 holonomy manifolds, and explores their connection to wrapped M5-branes.

Findings

Massless M3-brane solutions preserving supersymmetry.

Deformations of G_2 holonomy backgrounds.

Existence of M5-branes wrapped over S^2.

Abstract

We construct supersymmetric M3-brane solutions in D=11 supergravity. They can be viewed as deformations of backgrounds taking the form of a direct product of four-dimensional Minkowski spacetime and a non-compact Ricci-flat manifold of G_2 holonomy. Although the 4-form field strength is turned on it carries no charge, and the 3-branes are correspondingly massless. We also obtain 3-branes of a different type, arising as M5-branes wrapped over S^2.