The “Multiverse” according to Melvyn Bragg with Martin Rees, from In Our Time, BBC Radio 4, 21 Feb 2008.

Melvyn Bragg with Martin Rees, President of the Royal Society and Professor of Cosmology and Astrophysics at the University of Cambridge, Fay Dowker, Reader in Theoretical Physics at Imperial College, Bernard Carr, Professor of Mathematics and Astronomy at Queen Mary, University of London.

Beginning at 18:14 minutes into pod cast in response to a question about the anthropic principal Carr states:
“Yes, the point is that there are various forces in nature and these each have a particular strength – they are called the coupling constants. And we don’t know, we cannot predict what the strengths of those couplings constants are, at least we can’t with present physics. But what is found is that there are relationships between those constants which seem to be required in order that we can be here. In order that galaxies can form, and stars can form, and chemistry can form and ultimately therefore, that human beings and intelligent beings can form and ask these sorts of questions. You have to have these fine tunings between these constants of nature. And it is not just these coupling constants it’s the masses of elementary particles – it’s the cosmological constant which describes the acceleration of the universe. Now, known physics does not explain these fine tunings. It seems indisputable that these relationships are required in order that life can arise. And they are really quite precise. They don’t determine constants uniquely, but they do determine constants to within something like say within ten percent. And there is simply no explanation.
And actually myself and Martin wrote a paper some thirty years ago, where we put all these coincidences together, pointing out that these fine tunings were required. Now at the time we made that suggestion it was not a very popular idea because it was regarded as a somewhat metaphysical explanation because there was no idea as why these fine – how these fine tunings would come about. I think there was maybe the suspicion that it hinted that there was some sort of fine tuner or God if you like, who must have created the universe in order for to make life arise. And that was very unpopular amongst most physicists because most physicists do not want to bring in a creator. So what’s been exciting about the multiverse, is that if you believe there is a multiverse where the constants are different, then it is fairly natural to say that there will be a small fraction of these universes in which the constants have the values which are required for life to arise. And so nowadays I think many cosmologists regard the multiverse as the sort of legitimisation of the anthropic principal because if there is only one universe then it is really rather hard to explain. But if you have got many, many universes then it is a natural selection effect that we have to be in a universe where the constants have the values required.”

From In Our Time, Transcribed by Randall Hardy. 21 February 2008

BBC podcasts:

Editorial Comment: It really showed what people are willing to believe in order to avoid admitting that there is a creator God. The speaker effectively admitted that the attraction of the multiverse theory is that it does away with the need to explain the anthropic principal in terms of a creator. Science to date has worked on the universe model which has Christian roots, i.e. one Creator, one set of laws, hence uni – verse.

Evidence News 9 July 2008