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Solitonic asymptotics for the Korteweg-de Vries equation in the small dispersion limit

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 نشر من قبل Tom Claeys
 تاريخ النشر 2009
  مجال البحث فيزياء
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We study the small dispersion limit for the Korteweg-de Vries (KdV) equation $u_t+6uu_x+epsilon^{2}u_{xxx}=0$ in a critical scaling regime where $x$ approaches the trailing edge of the region where the KdV solution shows oscillatory behavior. Using the Riemann-Hilbert approach, we obtain an asymptotic expansion for the KdV solution in a double scaling limit, which shows that the oscillations degenerate to sharp pulses near the trailing edge. Locally those pulses resemble soliton solutions of the KdV equation.



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