Physical theories are links between nomological variables and a primitive ontology. This is true for Newtonian mechanics, general relativity and quantum mechanics but also true for most alternative theories of gravitation, from Le Sage’s graviton to gravity as an entropic force. Assigning a cause to gravity is equivalent to making a metaphysical commitment about the nature of reality and this is ultimately related to whether our world is autonomous or not. Due to the theory underdetermination problem, we may never find out the true cause of gravity by experimentation alone.
The term “virtual” is used to describe the state of being such without actually being such. In this context, virtual reality can be defined as the state of being real without actually being real. The problem with such a definition is with the inference made about the state of reality or virtual reality.
A science presenter and comic, Steven Mould, not long ago made a video about a chain of beads that seem to defy gravity and levitate from a beaker. Actually this is a normal phenomenon but modeling its dynamics is not trivial. Most explanations do not take into account the mass of the beads because they are purely kinematic in nature but, obviously, a complete model of such phenomenon should do and whether the observed motion takes place clearly depends on the mass of the beads.