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arXiv · 1204.6407

La Grassmannienne non-linéaire comme variété fréchétique homogène

Mathieu Molitor
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Abstract

Let (M,g) be a compact Riemannian manifold of dimension n. For k \in {0,...,n}, we denote Gr_{k}(M) the set of compact, connected and oriented submanifolds of M of dimension k. This set is called the non-linear Grassmannian. In this article, we endow Gr_{k}(M) with a smooth Fréchet manifold structure and investigate its basic geometrical properties. In particular, if Σ\in Gr_{k}(M), we show that the space of smooth embeddings Emb(Σ,M) is the total space of principal fiber bundle with base space a collection of connected components of Gr_{k}(M). We also show that the connected components of Gr_{k}(M) are homogeneous with respect to the natural action of the group of diffeomorphisms of M.

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Mathieu Molitor. 2012-04-28. La Grassmannienne non-linéaire comme variété fréchétique homogène. https://arxiv.org/abs/1204.6407

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