(original review, 2000)
If there was an infinite number of universes wouldn't there be a universe in which a mad scientist had discovered how to destroy all the universes and pressed the button, so there would be nothing at all? But then there would also be a good scientist who devised a plan to stop the mad scientist from pressing the button in the first place! What if they are one & the same, who wins? But as with Madeira Island's Nationalism, the bad scientist would only have to succeed once.
Fine tuning suggests that the Universe is at it is because in effect that's how it has to be therefore the creator is not malevolent. Believers would believe that the Universe is fine tuned whilst atheists would not. Therefore Devil's Advocate likes attributing believers with atheist views to lay a charge of brutality malevolent when in actual fact the malevolent theory is their own. Devil's Advocate has missed the fact that if you don't believe in fine tuning and you don't believe in God then you are laying the blame for random cruelty on evolution. The reverse is not true because believers accept fine tuning:
- God + Belief + Fine tuning = No Malevolence (according to Dawkin’s argument);
- Atheism + randomness + evolution = Biology professor criticising the welfare state for allowing thick yobs too have too many kids.
So, is there a universe somewhere in which every Tom, Dick and Harry et al are decent talented principled intelligent informed people with nothing but social & environmental good at heart & in action? Ah, well, clearly the multiverse hypothesis has just been irrevocably debunked. Pity. Nah. Nor really. There are definitely multiverses. They exist on the far side of infinity. More importantly, did my cat Ilsa go to heaven? I'm not sure. Maybe she's God in a reverse multiverse. And perhaps (nay, certainly) also a universe in which the multiverse theory does not apply. (*head explodes*) But what do I know. I'm too thick to understand any of this. More importantly: Can Benfica win the Portuguese League this year, that's what I want to know. Sure can. In the universe 3 universes over, they win it with a team made up entirely of dachshunds!
Seriously, the many-worlds interpretation isn't really about the universe splitting per se, the goal is to avoid the problem of wavefunction collapse that is invoked in measurement. The principle of superposition means that we can create states that are, for example, half spin up and half spin down. When we make a measurement of the spin, the wavefunction collapses into only one of these states. However, these measurement processes are qualitatively different from unobserved processes, which allow the wavefunction to evolve smoothly with time. This has led to a lot of discussions about the role of observers in quantum mechanics (Schrödinger's cat, etc.). The basic idea of many worlds is that there is nothing special about measurement. The wavefunction only appears to collapse to the (necessarily quantum) observer, but all possible universes coexist in the same way that the states spin up and down can coexist for the electron.