Surely I’m not alone in thinking recent developments in string theory validate it beyond reasonable doubt?
It’s been some years since Polchinski’s (sp) 2000 paper that suggested string theory has 10exp500 solutions (give or take a few powers of 10) and that all are valid solutions. Some scientists think this kills the theory somewhat, since only one of these would apply to ‘our’ universe.
But assuming (admittedly quite an assumption) David Deutsch’s theory that the Multiverse contains an infinity of universes only visible to each other by the quantum shadows of electrons etc, surely this adds support to string theory BEING a theory of everything – it explains every possible universe, and also explains why our particular universe is the way it is.
Figures. Why should there be anything special about our universe? It just happens to fit the development of carbon-based life. Just as in past centuries it’s been demonstrated that Earth’s nothing special (we just happen to live here), and the sun’s nothing special as stars go (we just happen to revolve around it). Nor is our solar system much to write home about (others have planets too), and the Milky Way’s just a galaxy. (And a chocolate bar. Actually, Galaxy’s a chocolate bar too, but confectionery doesn’t need to be scientifically consistent.)
Alter that cosmological constant just a smidgeon, and you’ve got a bunch of weird universes, all of which will appear in that 10exp500.
In my view, the discovery that the cosmo constant is non-zero sews up the case for string theory: it suggests that the whole of physics doesn’t need to be mathematically ‘whole’, that there’s a bit left over at the edges. And it’s equally interesting that the total number of solutions to string theory, while large, does not appear to be infinite.
And the weirdest thing of all – it seems some of those alternate universes actually exist in ‘our’ reality, not in parallel ‘dimensions’. Albeit beyond anywhere we could actually get to. But it’s a seriously kooky thought – there are regions to which we could theoretically travel that are governed by a different set of textbooks.
First time I read about string theory, something about it just ‘felt right’ although I couldn’t get to grips with the maths at all. While I realise this makes me no better than god-botherers in that I’m going in on faith – I really, really think string theory will eventually explain all of physics.
But on the thought that got me started on this. Does anyone know if the symbol used for the cosmo constant is the same one Einstein used before he rejected it? It’d be nice to have some terminological continuity for the cosmological constant.
(And yes, this whole blog was leading up to that last sentence, because I don’t think I can ever use it again.)