Troels Harmark

The SU(2) x SU(2) sector in the string dual of N=6 superconformal Chern-Simons theory

We examine the string dual of the recently constructed N=6 superconformal Chern–Simons theory of Aharony, Bergman, Jafferis and Maldacena (ABJM theory). We focus in particular on the SU(2)×SU(2) sector. We find a sigma-model limit in which the resulting sigma-model is two Landau–Lifshitz models added together. We consider a Penrose limit for which we can approach the SU(2)×SU(2) sector. Finally, we find a new Giant Magnon solution in the SU(2)×SU(2) sector corresponding to one magnon in each SU(2). We put these results together to find the full magnon dispersion relation and we compare this to recently found results for ABJM theory at weak coupling.

Essentials of blackfold dynamics

We develop and significantly generalize the effective worldvolume theory for higher-dimensional black holes recently proposed by the authors. The theory, which regards the black hole as a black brane curved into a submanifold of a background spacetime — a blackfold—, can be formulated in terms of an effective fluid that lives on a dynamical worldvolume. Thus the blackfold equations split into intrinsic (fluid-dynamical) equations, and extrinsic (generalized geodesic embedding) equations. The intrinsic equations can be easily solved for equilibrium configurations, thus providing an efficient formalism for the approximate construction of novel stationary black holes. Furthermore, it is possible to study time evolution. In particular, the long-wavelength component of the Gregory-Laflamme instability of black branes is obtained as a sound-mode instability of the effective fluid. We also discuss action principles, connections to black hole thermodynamics, and other consequences and possible extensions of the approach. Finally, we outline how the fluid/AdS-gravity correspondence is related to this formalism.

Stationary and axisymmetric solutions of higher-dimensional general relativity

We study stationary and axisymmetric solutions of General Relativity, i.e., pure gravity, in four or higher dimensions.

World-Volume Effective Theory for Higher-Dimensional Black Holes

D

Instabilities of black strings and branes

-dimensional stationary and axisymmetric solutions are defined as having

Finite size Giant Magnons in the string dual of N=6 superconformal Chern-Simons theory

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New horizons for black holes and branes

commuting Killing vector fields. We derive a canonical form of the metric for such solutions that effectively reduces the Einstein equations to a differential equation on an axisymmetric

Black Holes on Cylinders

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Supergravity and space-time non-commutative open string theory

by

Heating up the BIon

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