We investigate the Spin(7) holonomy metric of cohomogeneity one with the principal orbit SU(3)/U(1). A choice of U(1) in the two dimensional Cartan subalgebra is left as free and this allows manifest Σ3 = W (SU(3)) (= the Weyl group) symmetric formulation. We find asymptotically locally conical (ALC) metrics as octonionic gravitational instantons. Complex projective space CP(2) that is a supers...

We solve the Killing spinor equations of N = 1 supergravity, with four supercharges, coupled to any number of vector and scalar multiplets in all cases. We find that backgrounds with N = 1 supersymmetry admit a null, integrable, Killing vector field. There are two classes of N = 2 backgrounds. The spacetime in the first class admits a parallel null vector field and so it is a pp-wave. The space...

The volumes, spectra and geodesics of a recently constructed infinite family of fivedimensional inhomogeneous Einstein metrics on the two S bundles over S are examined. The metrics are in general of cohomogeneity one but they contain the infinite family of homogeneous metrics T . The geodesic flow is shown to be completely integrable, in fact both the Hamilton-Jacobi and the Laplace equation se...

The equations of 10 or 11 dimensional supergravity admit supersymmetric compactifications on 7-manifolds of G2 holonomy, but these supergravity vacua are deformed away from special holonomy by the higher-order corrections of string or M-theory. We find simple expressions for the first-order corrections to the Einstein and Killing spinor equations in terms of the calibrating 3-form of the leadin...

For a compact connected Lie group G acting as isometries of cohomogeneity not equal to 0 or 2 on orientable Riemannian manifold $$M^{n+1},$$ we prove the existence nontrivial embedded G-invariant minimal hypersurface, that is smooth outside set Hausdorff dimension at most $$n-7.$$

As a means to better understanding manifolds with positive curvature, there has been much recent interest in the study of nonnegatively curved manifolds which contain either a point or an open dense set of points at which all 2-planes have positive curvature. We study infinite families of biquotients defined by Eschenburg and Bazaikin from this viewpoint, together with torus quotients of S × S....

We consider the nonlinear stability of the Kaluza-Klein monopole viewed as the static solution of the five-dimensional vacuum Einstein equations. Using both numerical and analytical methods, we give evidence that the Kaluza-Klein monopole is asymptotically stable within the cohomogeneity-two biaxial Bianchi type-IX ansatz recently introduced by Bizoń, Chmaj, and Schmidt. We also show that for s...