Faced with the design argument from the fine tuning of the cosmos, many atheists retreat to an ad hoc multiplication of the available probabilistic resources called the 'many worlds' or 'multiverse' hypothesis. However,as Brian Green, physicist and mathematician at Columbia University, and author of The Fabric of the Cosmos, points out, positing unlimited probabilistic resources is a science stopper (which, interestingly, is often an accusation laid at the doorstep of ID): If true, the idea of a multiverse would be a Copernican Revolution realized on a cosmic scale. It would be a rich and astounding upheaval, but one with potentially hazardous consequences. Beyond the inherent difficulty in assessing its validity, when should we allow the multiverse framework to be invoked in lieu of a more traditional scientific explanation? Had this idea surfaced a hundred years ago, might researchers have chalked up various mysteries to how things just happen to be in our corner of the multiverse and not pressed on to discover all the wondrous science of the last century? …The danger, if the multiverse idea takes root, is that researchers may too quickly give up the search for underlying explanations. When faced with seemingly inexplicable observations, researchers may invoke the framework of the multiverse prematurely – proclaiming some phenomenon or other to merely reflect conditions in our own bubble universe and thereby failing to discover the deeper understanding that awaits us.[i]
[i] Brian Green, ‘The Multiverse’, John Brockman (ed.), What’s Your Dangerous Idea?, (Pocket Books, 2006), p. 120-121.