A proof is offered for the equivalence of the energy velocity and the group velocity in the case where the group velocity may be negative while the wavenumber is positive. The explicit expression for both the energy ...A proof is offered for the equivalence of the energy velocity and the group velocity in the case where the group velocity may be negative while the wavenumber is positive. The explicit expression for both the energy velocity and the group velocity is obtained for waves in an isotropic homogeneous plate waveguide. Calculations show the values of the group velocity or the energy velocity to be negative for some frequencies.展开更多
文摘A proof is offered for the equivalence of the energy velocity and the group velocity in the case where the group velocity may be negative while the wavenumber is positive. The explicit expression for both the energy velocity and the group velocity is obtained for waves in an isotropic homogeneous plate waveguide. Calculations show the values of the group velocity or the energy velocity to be negative for some frequencies.
