I don’t know much anything about relativity, but waves on a grid in computational fluid dynamics (CFD for short) typically don’t have the problem you describe.
Not even for wavelengths not much longer than the grid spacing?
I don’t see how that would be a problem. Perhaps I’m missing something, so if you could explain I’d be appreciative.
Usually the problem is that wavelengths smaller than the grid size obviously can’t be resolved. A class of turbulence modeling approaches can help with that to a certain extent. This class of methods is called “large eddy simulation”, or LES for short. You apply a low pass filter to the governing equations and then develop models for “unclosed” terms. In practice this is typically done less rigorously than I’d like, but it’s a valid modeling approach in general that should see more use in other fields. (Turbulence modeling is an interesting field in itself that a rational person might be interested in studying simply for the intellectual challenge.)
Not even for wavelengths not much longer than the grid spacing?
I don’t see how that would be a problem. Perhaps I’m missing something, so if you could explain I’d be appreciative.
Usually the problem is that wavelengths smaller than the grid size obviously can’t be resolved. A class of turbulence modeling approaches can help with that to a certain extent. This class of methods is called “large eddy simulation”, or LES for short. You apply a low pass filter to the governing equations and then develop models for “unclosed” terms. In practice this is typically done less rigorously than I’d like, but it’s a valid modeling approach in general that should see more use in other fields. (Turbulence modeling is an interesting field in itself that a rational person might be interested in studying simply for the intellectual challenge.)