Nah, it's just dependent on your definition of 'nothing'."Virtual" particles are real, are experimentally demonstrated by the well known Casimir plates experiment, and arise spontaneously from quantum fluctuations in spacetime.
If you think that 'there is no possible experiment', then you're just wrong. The experiment was proposed in 1948, and has been performed with increasing accuracy by various teams between 1958 and the present day; The observed results match Casimir's predictions.
That's just mistaking not knowing where the virtual particles come from with them coming from nowhere (or nothing).
If spacetime at its energy minimum is 'nothing' then virtual particles are something from nothing.
If spacetime itself is 'something', then 'nothing' is nowhere and never. It's hard to imagine how even a zero-point spacetime vacuum could arise from nowhere and never. 'From' doesn't even make sense in the absence of spacetime.
That's a metaphysical question, and perhaps even an interesting one; But denying the reality of "virtual" particles (as Steve does in his OP) isn't metaphysics, it's just erroneous physics.
My definition of nothing is that it itself does not exist. If there was a state of nothingness, nothing would exist (as crazy as that sounds). In my opinion, because there is something (always has and always will be) that makes nothingness not exist which is how it is to be. Yeah I know this sounds stupid.
Edit: to sound even crazier. We have something as a result of nothing. In order for nothing to be something must be. They have a very close nit relationship.