arXiv subjects

Emily J. Hackett-Jones

Publications and source records attributed to Emily J. Hackett-Jones.

3 recordsLinked to original sources

arXiv2004

Type IIB Killing spinors and calibrations

In this paper we derive the full set of differential equations and some algebraic relations for p-forms constructed from type IIB Killing spinors. These equations are valid for the most general type IIB supersymmetric backgrounds which have a non-zero NS-NS 3-form field strength, H, and non-zero R-R field strengths, G^{(1)}, G^{(3)} and G^{(5)}. Our motivation is to use these equations to obtain generalised calibrations for branes in supersymmetric backgrounds. In particular, we consider giant gravitons in AdS_5 x S^5. These non-static branes have an interesting construction via holomorphic surfaces in C^{1,2} x C^3. We construct the p-forms corresponding to these branes and show that they satisfy the correct differential equations. Moreover, we interpret the equations as calibration conditions and derive the calibration bound. We find that giant gravitons minimise ``energy minus momentum''.

hep-th↗

arXiv2003

Topological charges for branes in M-theory

We propose a simple form for the superalgebra of M2 and M5-brane probes in arbitrary supersymmetric backgrounds of 11D supergravity, extending previous results in the literature. In particular, we identify the topological charges in the algebras and find BPS bounds for the energies. The charges are given by the integral over a brane's spatial worldvolume of a certain closed form built out of the Killing spinors and background fields. The existence of such closed forms for arbitrary supersymmetric backgrounds generalises the existence of calibration forms for special holonomy manifolds.

hep-th↗

arXiv2002

Giant gravitons as probes of gauged supergravity

We consider giant graviton probes of 11-dimensional supergravity solutions which are lifts of arbitrary solutions of 4-dimensional U(1)^4 and 7-dimensional U(1)^2 gauged supergravities. We show that the structure of the lift ansatze is sufficient to explicitly find a solution for the embedding and motion of the M5- or M2-brane in the internal space. The brane probe action then reduces to that of a massive charged particle in the gauged supergravity, demonstrating that probing the gauged supergravity with such particles is equivalent to the more involved 11-dimensional brane probe calculation. As an application of this we use these particles to probe superstar geometries which are conjectured to be sourced by giant gravitons.

hep-th↗