SIAM Journal on Applied Mathematics
In a previous paper, the authors showed how to construct certain solutions of the acoustic and electromagnetic wave equations in three dimensions, which are constrained asymptotically to a narrow conical sector of an outgoing spherical shell, i.e., which behave like “bullets.” In this paper, it is shownthat, in the acoustic case, the magnitude of the relative error between the true solution and its asymptotic form decays in time according to an inverse square root law.
Read More: https://epubs.siam.org/doi/10.1137/0153025
Moses, Harry E. and Prosser, Reese T., "Decay of the Relative Error in the Formation of Acoustic Bullets" (1993). Open Dartmouth: Faculty Open Access Articles. 2469.