tag:blogger.com,1999:blog-37936507.post6413823582364640752..comments2023-08-08T10:25:47.529+01:00Comments on McCabism: The tree of life?Gordon McCabehttp://www.blogger.com/profile/09151162643523937086noreply@blogger.comBlogger2125tag:blogger.com,1999:blog-37936507.post-31228758978323999872009-01-22T21:53:00.000+00:002009-01-22T21:53:00.000+00:00Smolin responded to the Rothman-Ellis criticisms i...Smolin responded to the Rothman-Ellis criticisms in his 1997 book, <EM>The Life of the Cosmos</EM>, (p306-307). <BR/><BR/>Perhaps more seriously, Vilenkin has recently pointed out that in universes which expand forever, such as our own now appears to be, an infinite number of black holes will pop into existence due to random thermal fluctuations. This mechanism of black hole production is more fecund than that from the collapse of stars. Moreover, the production rate of such black holes is increased by raising the value of the cosmological constant from the value which we observe in our own universe. Hence, our own universe is not optimised for black hole production.<BR/><BR/>If you're interested, Smolin responds to Vilenkin here:<BR/><BR/>http://arxiv.org/PS_cache/hep-th/pdf/0612/0612185v1.pdfGordon McCabehttps://www.blogger.com/profile/09151162643523937086noreply@blogger.comtag:blogger.com,1999:blog-37936507.post-39301624891345011972009-01-22T14:21:00.000+00:002009-01-22T14:21:00.000+00:00I recently read that Smolin's idea of cosmic natur...I recently read that Smolin's idea of cosmic natural selection has been challenged as it has become apparent that life permitting (stable star) universes are less likely to be ones that produce many black holes, not more likely as he assumed. In other words, Smolin's theory would actually weed out life permitting universes not make them more likely in a natural selection kind of way. Is this right? (The reference is Rothman and Ellis, Quarterly Journal of the Royal Astronomical Society 34 (1992) though I've not actually read it myself.)Anonymousnoreply@blogger.com