Scientists seek a single description of reality. But modern physics allows for many different descriptions, many equivalent to one another, connected through a vast landscape of mathematical possibility.
The current Standard Model of particle physics is indeed a tightly constructed mechanism with only a handful of ingredients. Yet instead of being unique, the universe seems to be one of an infinitude of possible worlds. We have no clue why this particular combination of particles and forces underlies nature’s structure. Why are there six “flavors” of quarks, three “generations” of neutrinos, and one Higgs particle? Furthermore, the Standard Model comes with 19 constants of nature — numbers like the mass and charge of the electron — that have to be measured in experiments. The values of these “free parameters” seem to be without any deeper meaning. On the one hand, particle physics is a wonder of elegance; on the other hand, it is a just-so story.
If our world is but one of many, how do we deal with the alternatives? The current point of view can be seen as the polar opposite of Einstein’s dream of a unique cosmos. Modern physicists embrace the vast space of possibilities and try to understand its overarching logic and interconnectedness. From gold diggers they have turned into geographers and geologists, mapping the landscape in detail and studying the forces that have shaped it.
The game changer that led to this switch of perspective has been string theory. More.
What a surprise.
While giving the usual 1995 justification for the “M-theory” conjecture of a unique string theory, Dijkgraaf neglects to mention that, 23 years later, no one has a viable proposal for what this unique theory might be. He mentions none of the problems of moduli stabilization, or that the theorists “mapping the landscape in detail” don’t actually know what equations govern this supposed landscape and thus have hit a dead-end, unable to predict anything about anything.
The argument seems to be that we need to throw out our highly successful quantum field theories, replacing them with a “radical new framework” describing “impenetrable complexity”. But what is this “radical new framework”? As best I can tell, what’s now popular at the IAS is the “it from qubit” idea that is the topic of this summer’s PITP program. More.
Well, throwing things out, whether those things are ideas or biology profs, is now Cool. Rationality is on the run everywhere. Check out the invasion of the sciences by post-modernism and the feeble response from Big Science.
How string theory can be a theory of everything. That’s so typical. It’s either a theory of everything or a theory of nothing. Such grandeur can easily do without much evidence.