We present a review of gravitating particle-like and black hole solutions with non-Abelian gauge fields. The emphasis is given to the description of the structure of the solutions and to the connection with the results of flat space soliton physics. We describe the Bartnik-McKinnon solitons and the non-Abelian black holes arising in the Einstein-Yang-Mills theory, and consider their various generalizations. These include axially symmetric and slowly rotating configurations, solutions with higher gauge groups, Λ-term, dilaton, and higher curvature corrections. The stability issue is discussed as well. We also describe the gravitating generalizations for flat space monopoles, sphalerons, and Skyrmions.

We study the decays of the τ -sleptons (τ 1,2 ) and τ -sneutrino (ν τ ) in the Minimal Supersymmetric Standard Model (MSSM) with complex parameters A τ , µ and M 1 (U(1) gaugino mass). We show that the effect of the CP phases of these parameters on the branching ratios ofτ 1,2 andν τ decays can be quite strong in a large region of the MSSM parameter space. This could have an important impact on the search forτ 1,2 andν τ and the determination of the MSSM parameters at future colliders.So far most phenomenological studies on supersymmetric (SUSY) particle searches have been performed in the Minimal Supersymmetric Standard Model (MSSM) [1] with real SUSY parameters. Studies of the 3rd generation sfermions are particularly interesting because of the effects of the large Yukawa couplings. The lighter sfermion mass eigenstates may be relatively light and they could be thoroughly studied at an e − e + linear collider [2]. They could also be copiously produced in the decays of heavier SUSY particles. An analysis of the decays of the 3rd generation sleptonsτ 2 andν τ in the MSSM with real parameters was performed in Ref. [3], and phenomenological studies of production and decays of the 3rd generation sfermions at future e − e + colliders in Ref. [4]. The assumption that all SUSY parameters are real, however, may be too restrictive. The higgsino mass parameter µ and the trilinear scalar coupling parameters A f of the sfermionsf may be complex. In minimal Supergravity-type models the phase of µ (ϕ µ ) turns out to be restricted by the experimental data on electron and neutron electric dipole moments (EDMs) to a range |ϕ µ | < ∼ 0.1 − 0.2 for a universal scalar mass parameter M 0 < ∼ 400GeV, while the phase of the universal trilinear scalar coupling parameter A 0 is correlated with ϕ µ , but otherwise unrestricted [5]. In more general models the phases of the parameters A f of the 3rd generation sfermions are not restricted at one-loop level by the EDM data. However, there may be restrictions at two-loop level [6]. In a complete phenomenological analysis of production and decays of the SUSY particles one has to take into account that the µ and A f may be complex. Furthermore, explicit CP violation in the Higgs sector can be induced by loop effects involving CP-violating interactions of Higgs bosons to top and bottom squark (t andb) sector with complex parameters [7,8]. It is found [9] that such effects of the complex phases on the phenomenology of the Higgs boson search could be quite significant. In principle, the imaginary parts of the possible complex SUSY parameters involved could most directly and unambiguously be determined by measuring relevant CP-violating observables; e.g. such analyses in τ -slepton (τ ) pair production in e + e − and µ + µ − colliders were performed in Ref. [10]. On the other hand, the CP-conserving observables also can depend on the phases of the complex parameters because in general the mass-eigenvalues and the couplings of the SUSY particles (sparticles) involved are functions of the ...

We present new solutions to Einstein-Maxwell-dilaton-axion (EMDA) gravity in four dimensions describing black holes which asymptote to the linear dilaton background.In the non-rotating case they can be obtained as the limiting geometry of dilaton black holes. The rotating solutions (possibly endowed with a NUT parameter) are constructed using a generating technique based on the Sp(4, R) duality of the EMDA system. In a certain limit (with no event horizon present) our rotating solutions coincide with supersymmetric Israel-Wilson-Perjès type dilaton-axion solutions. In the presence of an event horizon supersymmetry is broken. The temperature of the static black holes is constant, and their mass does not depend on it, so the heat capacity is zero. We investigate geodesics and wave propagation in these spacetimes and find superradiance in the rotating case. Because of the non-asymptotically flat nature of the geometry, certain modes are reflected from infinity; in particular, all superradiant modes are confined. This leads to a classical instability of the rotating solutions. The non-rotating linear dilaton black holes are shown to be stable against spherical perturbations.