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MiS Preprint
95/2002
Structure of entropy solutions for multi--dimensional scalar conservation laws
Camillo De Lellis, Felix Otto and Michael Westdickenberg
Abstract
An entropy solution $u$ of a multi--dimensional scalar conservation law is not necessarily in $BV$, even if the conservation law is genuinely nonlinear. We show that $u$ nevertheless has the structure of a $BV$--function in the sense that the shock location is codimension--one rectifiable.
This result highlights the regularizing effect of genuine nonlinearity in a qualitative way; it is based on the locally finite rate of entropy dissipation. The proof relies on the geometric classification of blow--ups in the framework of the kinetic formulation.