[amelius]

> Laplace transformations are differential equations so I fail to see your point.

What I mean is that typically an electrical engineer will convert L and C elements to complex impedances (which depend on the frequency through s), and will then compute as though the elements are ordinary resistances. The expression "d/dt" isn't used in the entire analysis.

See: https://en.wikipedia.org/wiki/Phasor

Quoting:

> the phasor transform thus allows the analysis (calculation) of the AC steady state of RLC circuits by solving simple algebraic equations (albeit with complex coefficients) in the phasor domain instead of solving differential equations (with real coefficients) in the time domain

[jshowa1]

This is like saying that if I convert mph to m/s then it's not a speed anymore. It's still a differential equation, just in a different domain because you can convert back from the s-domain into the time one.