Return to Colloquia & Seminar listing

### On the nonlinear theory of sound

**Colloquium**

Speaker: | Robin Young, University of Massachussetts Amherst |

Related Webpage: | https://people.math.umass.edu/~young/ |

Location: | 1147 MSB |

Start time: | Tue, Feb 28 2023, 4:30PM |

I will discuss a proof of the existence of a large class of nonlinear sound waves, which are smooth, time periodic, oscillatory solutions to the 3x3 compressible Euler equations, in one space dimension. Being perturbations of solutions of a linear wave equation, these provide a rigorous justification for the centuries old theory of Acoustics. In particular, Riemann's celebrated 1860 proof that compressions always form shocks holds

onlyfor the degenerate cases of isentropic and isothermal flows.This is based on joint work with Blake Temple.