Author : Camillo De Lellis,Emanuele Nunzio Spadaro
Publisher : American Mathematical Soc.
Page : 92 pages
File Size : 54,8 Mb
Release : 2011
Category : Dirichlet principle
ISBN : 9780821849149
$Q$-Valued Functions Revisited by Camillo De Lellis,Emanuele Nunzio Spadaro Pdf
In this memoir the authors revisit Almgren's theory of $Q$-valued functions, which are functions taking values in the space $\mathcal{A}_Q(\mathbb{R}^{n})$ of unordered $Q$-tuples of points in $\mathbb{R}^{n}$. In particular, the authors: give shorter versions of Almgren's proofs of the existence of $\mathrm{Dir}$-minimizing $Q$-valued functions, of their Holder regularity, and of the dimension estimate of their singular set; propose an alternative, intrinsic approach to these results, not relying on Almgren's biLipschitz embedding $\xi: \mathcal{A}_Q(\mathbb{R}^{n})\to\mathbb{R}^{N(Q,n)}$; improve upon the estimate of the singular set of planar $\mathrm{D}$-minimizing functions by showing that it consists of isolated points.