What I most definitely have not done is independently invent the idea of a virtual universe. It’s an idea that has been growing over time and has been dealt with in different ways in such films as the Matrix, in several science fiction novels (most notably those by Philip K Dick) and even in my own short story Reality.
I guess it has its origins in philosophy and thought experiments concerning the simple question of how we know what we think is real is actually real. The philosophical position of solipsism owes its origins to this debate.
However, more recently it has become a subject of scientific rather than philosophical discussion. There’s a lot to be read about it on Wikipedia and elsewhere, but the gist of the debate is quite simple.
If it is possible to create a self-contained universe as a computer simulation in even one possible universe (assuming that there is more than one) and that universe could itself generate self-contained computer-generated universes which themselves could generate such virtual universes and so on ad infinitum, then there could very well be many more virtual than real universes. In that case, the probability .is that the universe that we know is more likely to be a computer simulation than the real thing. It is unlikely that there are infinitely many universes simply because of the nature of infinity, but there could be an astronomically large number and by far the greatest proportion of them (by a ratio measured perhaps in googolplexes) could be computer simulations.
This is fascinating stuff, only held in check by the very real likelihood that this is all fantasy and that it is simply mathematically and physically impossible for this to be the case. For instance, perhaps the necessary computational power cannot be contained in an external universe.
But it’s fun to speculate…