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arXiv · 1002.2911

A note on propagation of singularities of semiconcave functions of two variables

Ludek Zajicek
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Abstract

P. Albano and P. Cannarsa proved in 1999 that, under some applicable conditions, singularities of semiconcave functions in $\R^n$ propagate along Lipschitz arcs. Further regularity properties of these arcs were proved by P. Cannarsa and Y. Yu in 2009. We prove that, for $n=2$, these arcs are very regular: they can be found in the form (in a suitable Cartesian coordinate system) $ψ(x) = (x, y_1(x)-y_2(x)), x \in [0,α]$, where $y_1$, $y_2$ are convex and Lipschitz on $[0,α]$. In other words: singularities propagate along arcs with finite turn.

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Ludek Zajicek. 2010-02-15. A note on propagation of singularities of semiconcave functions of two variables. https://arxiv.org/abs/1002.2911

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