Let (with ) be vector fields of class in an open set , let be a -dimensional submanifold of and define where is the tangent space to at . Then we expect the following property, which is obvious in the special case when is an interior point (relative to ) of : If is a -density point (relative to ) of then all the iterated Lie brackets of order less or equal to
Using a result of J.-M. Bony, we prove the weak involutivity of truncated microsupports. More precisely, given a sheaf on a real manifold and , if two functions vanish on , then so does their Poisson bracket.
In this article, we formalize isometric differentiable functions on real normed space [17], and their properties.
In the paper under review, the author presents some results on the basis of the Nash-Gromov theory of isometric immersions and illustrates how the same results and ideas can be extended to other structures.
In this paper we study isometry-invariant Finsler metrics on inner product spaces over or , i.e. the Finsler metrics which do not change under the action of all isometries of the inner product space. We give a new proof of the analytic description of all such metrics. In this article the most general concept of the Finsler metric is considered without any additional assumptions that are usually built into its definition. However, we present refined versions of the described results for more specific...
We construct the first examples of continuous families of isospectral Riemannian metrics that are not locally isometric on closed manifolds , more precisely, on , where is a torus of dimension and is a sphere of dimension . These metrics are not locally homogeneous; in particular, the scalar curvature of each metric is nonconstant. For some of the deformations, the maximum scalar curvature changes during the deformation.
We study the special Lagrangian Grassmannian , with , and its reduced space, the reduced Lagrangian Grassmannian . The latter is an irreducible symmetric space of rank and is the quotient of the Grassmannian under the action of a cyclic group of isometries of order . The main result of this paper asserts that the symmetric space possesses non-trivial infinitesimal isospectral deformations. Thus we obtain the first example of an irreducible symmetric space of arbitrary rank , which is...