Resonant mass detectors of GWs of spherical shape constitute the fourth generation of such kind of antennae, and are scheduled to start operation in the near future. In this communication I present a general description of the fundamental principles underlying the physics of this kind of detector, as well as of the motion sensor set suitable to retrieve the information generated by the incidence of a GW on the antenna.
We define on an ordered semi simple symmetric space a family of spherical functions by an integral formula similar to the Harish-Chandra integral formula for spherical functions on a Riemannian symmetric space of non compact type. Associated with these spherical functions we define a spherical Laplace transform. This transform carries the composition product of invariant causal kernels onto the ordinary product. We invert this transform when is a complex group, a real form of , and when ...
We study the action of a real-reductive group on a real-analytic submanifold of a Kähler manifold. We suppose that the action of extends holomorphically to an action of the complexified group on this Kähler manifold such that the action of a maximal compact subgroup is Hamiltonian. The moment map induces a gradient map . We show that almost separates the –orbits if and only if a minimal parabolic subgroup of has an open orbit. This generalizes Brion’s characterization of spherical...
This paper deals with Dirac, twistor and Killing equations on Weyl manifolds with -spin structures. A conformal Schrödinger-Lichnerowicz formula is presented and used to derive integrability conditions for these equations. It is shown that the only non-closed Weyl manifolds of dimension greater than 3 that admit solutions of the real Killing equation are 4-dimensional and non-compact. Any Weyl manifold of dimension greater than 3, that admits a real Killing spinor has to be Einstein-Weyl.
In his famous five variables paper Elie Cartan showed that one can canonically associate to a generic rank 2 distribution on a 5 dimensional manifold a Cartan geometry modeled on the homogeneous space , where is one of the maximal parabolic subgroups of the exceptional Lie group . In this article, we use the algebra of split octonions to give an explicit global description of the distribution corresponding to the homogeneous model.