Turok explains that the “large bandwagon” of the last 30 years has not found experimental support. The bandwagon in question is the Standard Model of particle physics established in the 1970s, which, he says, people have been elaborating ever since. “Grand unified theories, supersymmetry, string theory, M-theory, multiverse theory,” he lists. “Each is not particularly radical, but is becoming ever more complex and arbitrary.”
To illustrate the lack of experimental support for these ideas, Turok describes how many people were hoping string theory would represent a radical development; but since string theory – as currently interpreted – leads to the multiverse, Turok describes it as the “least predictive theory ever”.
Indeed, experimental support has not been found for other extensions of the Standard Model either. “We have discovered the Higgs and nothing else,” says Turok, “yet the vast majority of theorists had been confidently predicting WIMPS (weakly interacting massive particles) and supersymmetric particles…Theorists are walking around in a bit of a stunned silence.” He adds that it could turn out to be right that all sorts of other particles are needed along with the Higgs – but that thought seems to be misguided.
“My view is that this has been a kind of catastrophe – we’ve lost our way,” he says. “What we need are ideas as simple and radical as in the start of the 20th century with quantum mechanics.”
So what might these ideas look like? Turok explains how observations have shown that the universe is simpler than we ever expected – in contrast to our theories, which are becoming ever more complex.
It’s great to see this, very encouraging to think that a more reality-based point of view on fundamental physical theory may finally be emerging. My only criticism is that the program doesn’t seem to include any mathematics or mathematicians (except perhaps in the context of history and Emmy Noether). If you have a structure you don’t understand, which is unusually simple, with surprising explanatory power, you might want to ask mathematicians about it…
There is no difference that we know right now … between the story of divine intervention and the multiverse.
It’s great to see a conference on fundamental physics where the multiverse is coming in for some appropriate skepticism.