Abstract
A class of evolution equations in divergence form is studied in this paper. Specifically, we develop conditions under which the spatial divergence term, the flux, corresponds to the characteristic of a conservation law. The KdV equation is a prominent example of an equation having a flux term that is also a characteristic for a conservation law. We show that the flux term must be selfadjoint. General equations for the corresponding conservation laws and Hamiltonian densities are derived and supplemented with examples.
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2000 Mathematics Subject Classification:
primary 35K

(Metadata: XML, RSS, BibTeX) 
MathSciNet:
MR2378148 
Z'blattMATH:
pre05243890 
^{†}indicates author for correspondence 
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