Effective action of (massive) IIA on manifolds with SU(3) structure

In this paper we consider compactifications of massive type IIA supergravity on manifolds with SU(3) structure. We derive the gravitino mass matrix of the effective four-dimensional N = 2 theory and show that vacuum expectation values of the scalar fields naturally induce spontaneous partial supersymmetry breaking. We go on to derive the superpotential and the Kaehler potential for the resulting N = 1 theories. As an example we consider the SU(3) structure manifold SU(3)/U(1)xU(1) and explicitly find N = 1 supersymmetric minima where all the moduli are stabilised at non-trivial values without the use of non-perturbative effects.Comment: 25 pages, 2 figures. References added and typos corrected to match published versio

Non-Abelian black holes: The inside story

Recent progress in understanding of the internal structure of non-Abelian black holes is discussed. Talk given at the international Workshop on The Internal Structure of Black Holes and Spacetime Singularities, Haifa, Israel, June 29 -- July 3, 1997.Comment: 23 pages, latex, contains 12 eps files combined in 8 figure

Monopoles and the Emergence of Black Hole Entropy

One of the remarkable features of black holes is that they possess a thermodynamic description, even though they do not appear to be statistical systems. We use self-gravitating magnetic monopole solutions as tools for understanding the emergence of this description as one goes from an ordinary spacetime to one containing a black hole. We describe how causally distinct regions emerge as a monopole solution develops a horizon. We define an entropy that is naturally associated with these regions and that has a clear connection with the Hawking-Bekenstein entropy in the critical black hole limit.Comment: 6 pages, one figure RevTe

Static Cosmological Solutions of the Einstein-Yang-Mills-Higgs Equations

Numerical evidence is presented for the existence of a new family of static, globally regular `cosmological' solutions of the spherically symmetric Einstein-Yang-Mills-Higgs equations. These solutions are characterized by two natural numbers ($m\geq 1$, $n\geq 0$), the number of nodes of the Yang-Mills and Higgs field respectively. The corresponding spacetimes are static with spatially compact sections with 3-sphere topology.Comment: 7 pages, 5 figures, LaTe

Gravitating BPS Monopoles in all d=4p Spacetime Dimensions

We have constructed, numerically, both regular and black hole static solutions to the simplest possible gravitating Yang-Mills--Higgs (YMH) in $4p$ spacetime dimensions. The YMH systems consist of $2p-$th power curvature fields without a Higgs potential. The gravitational systems consist of the `Ricci scalar' of the $p-$th power of the Riemann curvature. In 4 spacetime dimensions this is the usual Einstein-YMH (EYMH) studied in \cite{Breitenlohner:1991aa, Breitenlohner:1994di}, whose qualitative results we emulate exactly.Comment: 31 pages, 9 figure

Dynamics of Gravitating Magnetic Monopoles

According to previous work on magnetic monopoles, static regular solutions are nonexistent if the vacuum expectation value of the Higgs field $\eta$ is larger than a critical value $\eta_{{\rm cr}}$, which is of the order of the Planck mass. In order to understand the properties of monopoles for $\eta>\eta_{{\rm cr}}$, we investigate their dynamics numerically. If $\eta$ is large enough ($\gg\eta_{{\rm cr}}$), a monopole expands exponentially and a wormhole structure appears around it, regardless of coupling constants and initial configuration. If $\eta$ is around $\eta_{{\rm cr}}$, there are three types of solutions, depending on coupling constants and initial configuration: a monopole either expands as stated above, collapses into a black hole, or comes to take a stable configuration.Comment: 11 pages, revtex, postscript figures; results for various initial conditions are added; to appear in Phys. Rev.

Mass inflation inside non-Abelian black holes

The interior geometry of static, spherically symmetric black holes of the Einstein-Yang-Mills-Higgs theory is analyzed. It is found that in contrast to the Abelian case generically no inner (Cauchy) horizon is formed inside non-Abelian black holes. Instead the solutions come close to a Cauchy horizon but then undergo an enormous growth of the mass function, a phenomenon which can be termed `mass inflation' in analogy to what is observed for perturbations of the Reissner-Nordstr{ø}m solution. A significant difference between the theories with and without a Higgs field is observed. Without a Higgs field the YM field induces repeated cycles of mass inflation -- taking the form of violent `explosions' -- interrupted by quiescent periods and subsequent approaches to an almost Cauchy horizon. With the Higgs field no such cycles occur. Besides the generic solutions there are non-generic families with a Schwarzschild, Reissner-Nordstr{ø}m and a pseudo Reissner-Nordstr{ø}m type singularity at $r=0