> He observed that classical physics, which makes use of the concept of real numbers, cannot be simulated by a Turing machine, which can only represent computable reals. Deutsch proposed that quantum computers may actually obey the CTD principle, assuming that the laws of quantum physics can completely describe every physical process.
I don’t necessarily feel like arguing further about this tiny issue, or a distraction about your misconceptions regarding quantum computing[1]; this problem has been widely discussed since Deutsch and there are plenty of sources out there. The point is that it takes a huge cognitive leap to suggest that consciousness is either fundamentally spiritual, or part of a (hypothetical) class of physics problems that can’t be solved by a computer.
[1] Quantum computers are real. You are confused by news stories about private companies with outlandish claims of powerful quantum computers. In physics laboratories, small quantum computers have existed for a few decades. Typically they are too small to do anything useful (I saw one in person that could factor any positive integer... if it was less than 15).
To me this argument is like saying, "Science shows that cold fusion could certainly provide the energy needed for an antigravity machine".
I'm not qualified to say whether that middle inductive step with this Church-Turing-Deutsch principle really holds or not, but I do know that neither quantum computing nor consciousness are well-understood, rigorously defined things.