A Blow-up Theorem for regular hypersurfaces on nilpotent - download pdf or read online

By Valentino Magnani

We receive an intrinsic Blow-up Theorem for normal hypersurfaces on graded nilpotent teams. This approach permits us to symbolize explicitly the Riemannian floor degree when it comes to the round Hausdorff degree with recognize to an intrinsic distance of the gang, particularly homogeneous distance. We follow this consequence to get a model of the Riemannian coarea forumula on sub-Riemannian teams, that may be expressed by way of arbitrary homogeneous distances.We introduce the traditional type of horizontal isometries in sub-Riemannian teams, giving examples of rotational invariant homogeneous distances and rotational teams, the place the coarea formulation takes an easier shape. by way of an identical Blow-up Theorem we receive an optimum estimate for the Hausdorff size of the attribute set relative to C1,1 hypersurfaces in 2-step teams and we end up that it has finite Q − 2 Hausdorff degree, the place Q is the homogeneous size of the crowd.

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