Here are two articles about this paper that I wrote with Martin Rees.
Although still highly controversial, the "A-word" is not quite the
taboo that it used to be in physics circles.
This is from the Number 29 1997 issue of New scientist:
If you read the New Science article above, you noticed that it put the following twist on my results: we're somehow lucky. In the original paper, I suggest that we're not lucky at all. Rather, some superstring theories and chaotic inflation models predict that spacetimes with many different dimensionalities (up to 26, say) actually exist in exponentially large regions that are for all practical purposes causally disconnected. If you buy such a theory as well as my argument that all of the existing spacetimes except the 3+1-dimensional one are uninhabitable, then you could in principle have predicted that the spacetime you inhabit is 3+1-dimensional even before you'd opened your eyes and checked. If you were an extremely prodigal newborn baby, you could have paraphrased Descarte and said ``cogito, ergo spacetime has 3+1 qmap''. If you're a practical-minded string theorist, then the message is simply that you needn't worry if the 3+1 compactification doesn't just ``drop out'' of your calculations - your theory predicts that we'll observe 3+1 anyway.
This is from the XXX issue of Sky & Telescope, also based on this paper.
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