Formation of shocks in higher-order nonlinear dispersion PDEs: nonuniqueness and nonexistence of entropy

V. A. Galaktionov

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arXiv · 0902.1635

Formation of shocks in higher-order nonlinear dispersion PDEs: nonuniqueness and nonexistence of entropy

V. A. Galaktionov

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Abstract

It is shown that third-order 1D nonlinear dispersion equations admit single point gradient catastrophe, described by blow-up-type similarity solutions. After blow-up, the solutions admit shock wave-type self-similar extensions. Snce such extensions are not unique, this implies the principle nonuniqueness of shock-type solutions and also nonexistence of any entropy-type description of proper unique solutions. A difficult free-boundary setting, with extra conditions specified on shocks, are necessary to restore uniqueness in such problems.

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V. A. Galaktionov. 2009-02-10. Formation of shocks in higher-order nonlinear dispersion PDEs: nonuniqueness and nonexistence of entropy. https://arxiv.org/abs/0902.1635

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