Front Tracking for Scalar Conservation Laws with Spatially Heterogeneous Flux

Fuente: arXiv
Saved in:
Bibliographic Details
Main Author: Venkatesh, Parasuram
Format: Preprint
Published: 2025
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866912682568843264
author Venkatesh, Parasuram
author_facet Venkatesh, Parasuram
contents In this article, we propose a novel front tracking scheme for scalar conservation laws with spatially heterogeneous, uniformly convex flux and prove that approximations converge to the unique entropy solution. The main tools are Dafermos' generalised characteristics and Kruzkov's entropies. Crucially, our method handles fluxes where classical theory fails completely. As a concrete demonstration, we construct entropy solutions for a Cauchy problem with flux $f(x,u)=xu^2$, where bounded initial data can become unbounded in finite time, even on compact spatial domains. This finite-time blow-up violates the maximum principle, rendering all classical existence techniques--based on $L^{\infty}$ estimates and compactness--inapplicable. However, the flux $f(x,u(x,t))$ remains bounded despite $u$ blowing up, and our front tracking scheme exploits this to construct approximations that converge to an entropy solution.
format Preprint
id arxiv_https___arxiv_org_abs_2508_01814
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Front Tracking for Scalar Conservation Laws with Spatially Heterogeneous Flux
Venkatesh, Parasuram
Analysis of PDEs
35L03, 35L65 (Primary), 35A01 (Secondary)
In this article, we propose a novel front tracking scheme for scalar conservation laws with spatially heterogeneous, uniformly convex flux and prove that approximations converge to the unique entropy solution. The main tools are Dafermos' generalised characteristics and Kruzkov's entropies. Crucially, our method handles fluxes where classical theory fails completely. As a concrete demonstration, we construct entropy solutions for a Cauchy problem with flux $f(x,u)=xu^2$, where bounded initial data can become unbounded in finite time, even on compact spatial domains. This finite-time blow-up violates the maximum principle, rendering all classical existence techniques--based on $L^{\infty}$ estimates and compactness--inapplicable. However, the flux $f(x,u(x,t))$ remains bounded despite $u$ blowing up, and our front tracking scheme exploits this to construct approximations that converge to an entropy solution.
title Front Tracking for Scalar Conservation Laws with Spatially Heterogeneous Flux
topic Analysis of PDEs
35L03, 35L65 (Primary), 35A01 (Secondary)
url https://arxiv.org/abs/2508.01814