…is here. Great stuff.
One of the themes, which I totally agree with, is that quantum computation helps frame the whole “interpretations of quantum mechanics” boondoggle in a useful way. This topic was touched on also by Dave Bacon a few weeks ago.
Deutsch’s point of view, which I share, is that accepting quantum mechanics to be an objective description of reality logically implies the many-worlds picture.
This is the way I have always thought about quantum mechanics, and I certainly don’t have any problem, technical, philosophical or otherwise, with the objective reality of the variety of possible worlds. When we operate one of our machines, I always think of 2^16 (or however many qubits) universes, all with everything identical except the values of the 16 bits on the chip, all having objective reality. I am OK with the idea that my history most likely tracks through the universe with the correct answer if I set up my machine language correctly.
What I don’t get is why physicists, and specifically those that use quantum mechanics regularly, have a problem with the reality of the many-worlds implications of QM. It’s certainly the case that advances in science often reveal that things aren’t always what they seem, and that fundamental truths don’t have to be obvious. We are clearly extremely limited in our perceptive capabilities…why should we be confused or distressed if it turns out it’s hard for us to “pierce the veil” and see things as they are? And why should we be surprised if the true nature of things doesn’t always match our 5-sense grounded expectations?