We couldn't build quantum computers unless the universe were quantum and computing. We can build such machines because the universe is storing and processing information in the quantum realm. When we build quantum computers, we're hijacking that underlying computation in order to make it do things we want: little and/or/not calculations. We're hacking into the universe.
Seth LloydOf course, not everybody's willing to go out and do the experiments, but for the people who are willing to go out and do that, - if the experiments don't work, then it means it's not science.
Seth LloydIndeed, as the above calculation indicates, to take full advantage of the memory space available, the ultimate laptop must turn all its matter into energy.
Seth LloydIf you wanted to build the most powerful computer you could, you can't do better than including everything in the universe that's potentially available.
Seth Lloyd