  The irrotational motion of a compressible inviscid fluid is studied in the
field of analogue gravity, where its metric is compared to that in general
relativity, a fluid analogue of an evaporating black hole has been realized
experimentally, and there are symmetries related to the standard model. Here we
show the analogy also extends quantitatively to electromagnetic and quantum
mechanical phenomena. We discuss a candidate model to account for the number
and precision of these analogies.
