There are various physical models to make visible how a theory works, for example:
- Falaco solitons, see also here, where it is said that the swimming pool model corresponds to black holes and cosmic strings
- Water models of black holes
- A helium model of the early Universe
- Models how to visualize kinetic theory
- The well-known example of a stretchable rubber sheet to envision the way general relativity works
And there are of course many more examples. But in how far do these models give a good picture of reality (the rubber sheet model certainly does not)? Of course, it depends on the theory, which can be right or wrong or of which this isn't clear yet (also, what once was thought as a true theory can later be considered as wrong, and vice-versa). Are these models merely an aid or is there a "real" connection, correspondence or whatever you call it, to the world? Or is the only real thing the math of the theories (as propagated by Max Tegmark). I guess we (almost) never can tell (or is it the opposite?), but answers can be given and it is certainly discussable.