The reality options reduce to three:
1. Physical realism. That only the physical world exists and it does so by by itself alone.
2. Dualism. That the physical world exists but there is also a higher reality beyond it.
3. Virtualism. That the physical world is a construct created by something outside itself.
In physical realism, a self-existent physical world observes itself as it is – but how then does matter observe? And in a purely physical world, random events like radioactivity that by definition aren’t predicted by prior physical events shouldn’t happen.
In dualism, a real physical world is observed from a spiritual realm that also influences it but this God of the gaps only explains what is left after science advances, which every day gets smaller.
In virtualism, another reality generates the physical world we see like images on a screen that only exist in appearance. Opinion is divided on whether this “other” is:
1. Physical. In The Matrix movie, a virtual New York seemed real to its inhabitants who only knew it by information, just as we know ours. When the hero disconnects from the matrix he falls back into another world where post-nuclear machines feed people virtual input while farming them for energy in vats. The physical world he previously “lived in” was a construct created by programs in another physical world. In theory, this is possible as by the Church-Turing thesis a finite program can simulate any specifiable output (Tegmark, 2007) but in practice, trying to simulate even a few hundred atoms with a conventional computer:
“… would need more memory space that there are atoms in the universe as a whole, and would take more time to complete the task than the current age of the universe.” (Lloyd, 2006) p53.
Since even a computer as big as our universe couldn’t remotely do the job, this option is unlikely.
2. Mental. In this view, the physical world is a dream of the mind, e.g. in solipsism a self-existing observer dreams a world that isn’t there at all. The esse est percipi thesis, that the mind creates reality, is shown by optical illusions but that doesn’t imply no reality out there. As Einstein said, surely the moon exists when no-one watches it? Solipsism solves the quantum observer effect but it doesn’t generalize well because if I’m dreaming you, you’re just my pixels. And if no tree falls in a forest when no-one watches, how does history arise? Do we fabricate the millions of years of dinosaurs before we came along? If I am dreaming, why can’t I dream the body that I want? For these and other reasons this option is unlikely.
3. Quantum. In this view, quantum processing creates physical events that otherwise wouldn’t exist. Physics currently rejects this option because it gives:
“…no means of understanding the hardware upon which that software is running. So we have no way of understanding the real physics of reality.” (Deutsch, 1997)
To assume that only the physical is real so what isn’t physical can’t be real is the sort of circular logic science warns us against. It is illogical to assume an answer then prove it by that assumption. Yet it is true that quantum entities aren’t physical because they appear and disappear in physically impossible ways, tunnel through physically impassable barriers, ignore the speed of light limit on physical interactions and superpose in physically impossible ways, e.g. quantum theory describes currents going both ways round a circuit at once, which can’t happen in physical reality. But that quantum waves aren’t physical doesn’t mean they don’t exist or that we can’t study them, as we study gravity that we can’t see physically. To expect the quantum “hardware” that creates physical reality to follow the rules of what it creates makes no sense. The qubit of quantum processing is unlike the bit of physical processing for this reason.
That what isn’t physical doesn’t exist is an assumption not a fact. And that science can’t study what it can’t see is untrue, as quantum theory testifies. Quantum realism, that the quantum world creates the physical world, is both logically possible and scientifically acceptable, so this option is now explored.