I'm pretty skeptical about the whole field myself, but miniaturization would presumably come via some new (disruptive) hardware technology. IC's weren't made by miniaturizing vacuum tubes.
Of course (back to skepticism) it's not like no one thought to try using quantum mechanics and history is starting over at the 60's. Modern QC research comes after decades of ideas failing, throughout more recent times where we have been much more technologically knowledgeable versus the early days of computing.
Of course (back to skepticism) it's not like no one thought to try using quantum mechanics and history is starting over at the 60's. Modern QC research comes after decades of ideas failing, throughout more recent times where we have been much more technologically knowledgeable versus the early days of computing.