47 citations · 183 across the 14 of their papers we have counts for
16 papers
Cohomological lifting of multi-toric graphs
Kael Dixon, Thomas Bruun Madsen, Andrew Swann
We study -manifolds obtained from circle bundles over symplectic -manifolds with -symmetry. When the geometry is multi-Hamiltonian, we show how the compact par…
Multi-toric geometries with larger compact symmetry
Thomas Bruun Madsen, Andrew Swann
We study complete, simply-connected manifolds with special holonomy that are toric with respect to their multi-moment maps. We consider the cases where there is a connected non-Abe…
Instantons on flat space: Explicit constructions
Jason D. Lotay, Thomas Bruun Madsen
In this note, we revisit some well-known examples of instantons on flat space that were originally discovered in the physics literature. In particular, we explain how the basic ins…
Toric geometry of Spin(7)-manifolds
Thomas Bruun Madsen, Andrew Swann
We study -manifolds with an effective multi-Hamiltonian action of a four-torus. On an open dense set, we provide a Gibbons-Hawking type ansatz that describes such…
Toric geometry of -manifolds
Thomas Bruun Madsen, Andrew Swann
We consider -manifolds with an effective torus action that is multi-Hamiltonian for one or more of the defining forms. The case of -actions is found to be distinguished.…
Quaternionic geometry in dimension eight
Diego Conti, Thomas Bruun Madsen, Simon Salamon
We describe the 8-dimensional Wolf spaces as cohomogeneity one SU(3)-manifolds, and discover perturbations of the quaternion-kaehler metric on the simply-connected 8-manifold G_2/S…
Invariant torsion and G_2-metrics
Diego Conti, Thomas Bruun Madsen
We introduce and study a notion of invariant intrinsic torsion geometry which appears, for instance, in connection with the Bryant-Salamon metric on the spinor bundle over S^3. Thi…
Harmonic structures and intrinsic torsion
Diego Conti, Thomas Bruun Madsen
We discuss the construction of Sp(2)Sp(1)-structures whose fundamental form is closed. In particular, we find 10 new examples of 8-dimensional nilmanifolds that admit an invariant…
Half-flat structures on S^3xS^3
Thomas Bruun Madsen, Simon Salamon
We describe left-invariant half-flat SU(3)-structures on S^3xS^3 using the representation theory of SO(4) and matrix algebra. This leads to a systematic study of the associated coh…
The odd side of torsion geometry
Diego Conti, Thomas Bruun Madsen
We introduce and study a notion of `Sasaki with torsion structure' (ST) as an odd-dimensional analogue of Kähler with torsion geometry (KT). These are normal almost contact metric…
Closed forms and multi-moment maps
Thomas Bruun Madsen, Andrew Swann
We extend the notion of multi-moment map to geometries defined by closed forms of arbitrary degree. We give fundamental existence and uniqueness results and discuss a number of ess…
Spin(7)-manifolds with three-torus symmetry
Thomas Bruun Madsen
Metrics of exceptional holonomy are vacuum solutions to the Einstein equation. In this paper we describe manifolds with holonomy contained in Spin(7) preserved by a three-torus sym…
Homogeneous spaces, multi-moment maps and (2,3)-trivial algebras
Thomas Bruun Madsen, Andrew Swann
For geometries with a closed three-form we briefly overview the notion of multi-moment maps. We then give concrete examples of multi-moment maps for homogeneous hypercomplex and ne…
Multi-moment maps
Thomas Bruun Madsen, Andrew Swann
We introduce a notion of moment map adapted to actions of Lie groups that preserve a closed three-form. We show existence of our multi-moment maps in many circumstances, including…
Invariant strong KT geometry on four-dimensional solvable Lie groups
Thomas Bruun Madsen, Andrew Swann
A strong KT (SKT) manifold consists of a Hermitian structure whose torsion three-form is closed. We classify the invariant SKT structures on four-dimensional solvable Lie groups. T…
A Quark-Antiquark Condensate in Three-Dimensional QCD
P. H. Damgaard, U. M. Heller, A. Krasnitz +1
Three-dimensional lattice QCD is studied by Monte Carlo simulations within the quenched approximation. At zero temperature a quark-antiquark condensate is observed in the limit of…