We present a formula for the full Cheeger-Chern-Simons class of the tautological flat complex vector bundle of rank 2 over BSL(2, C). Our formula improves the formula in [DZ], where the class is onlyâ€¦ (More)

In this note, we consider the Dirac operator D on a Riemannian symmetric space M of noncompact type. Using representation theory, we show that D has point spectrum iff the Ã‚-genus of its compact dualâ€¦ (More)

We establish extremality of Riemannian metrics g with non-negative curvature operator on symmetric spaces M = G/K of compact type with rkG âˆ’ rkK â‰¤ 1. Let á¸¡ be another metric with scalar curvature ÎºÌ„,â€¦ (More)

The 2s-->3s transition of (6,7,8,9)Li was studied by high-resolution laser spectroscopy using two-photon Doppler-free excitation and resonance-ionization detection. Hyperfine structure splittings andâ€¦ (More)

PHELIX is a Petawatt high-energy laser for heavy-ion experiments that can deliver 1-10 ns long pulses at 1053 nm with energies up to 1 kJ to the ion beam target chamber at the Z6 experimental area orâ€¦ (More)

We compute the Eells-Kuiper invariant of the Berger manifold SO(5)/ SO(3) and determine that it is diffeomorphic to the total space of an S 3-bundle over S 4. This answers a question raised by K.â€¦ (More)

Let a Lie group G act isometrically on an odd dimensional Riemannian manifold M and let D be a G-equivariant operator of Dirac type on M. We construct a formal power series X (D) in X 2 g, which canâ€¦ (More)

Let D be a homogeneous Dirac operator on the quotient M = G=H of two compact connected Lie groups. We construct a deformation ~ D of D and calculate its equivariant-invariant G (~ D) explicitly onâ€¦ (More)

In this note, we look at estimates for the scalar curvature Îº of a Riemannian manifold M which are related to spin c Dirac operators: We show that one may not enlarge a KÃ¤hler metric with positiveâ€¦ (More)