  An interpretation of non-relativistic quantum mechanics is presented in the
spirit of Erwin Madelung's hydrodynamic formulation of QM and Louis de
Broglie's and David Bohm's pilot wave models. The aims of the approach are as
follows: 1) to have a clear ontology for QM, 2) to describe QM in a causal way,
3) to get rid of the wave-particle dualism in pilot wave theories, 4) to
provide a theoretical framework for describing creation and annihilation of
particles, and 5) to provide a possible connection between particle QM and
virtual particles in QFT. These goals are achieved, if the wave function is
replaced by a fluid of so called virtual particles. It is also assumed that in
this fluid of virtual particles exist a few real particles and that only these
real particles can be directly observed. This has relevance for the measurement
problem in QM and it is found that quantum probabilities arise in a very
natural way from the structure of the theory. The model presented here is very
similar to a recent computational model of quantum physics and recent Bohmian
models of QFT.
