Here are some quotes from Physics World’s interview with Neil Turok, the Institute’s director.
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. For example, Planck has mapped the CMB
(cosmic microwave background) sky and we have found that only two numbers are
needed to describe it. The hydrogen atom is another example of something that
can be described with a simple model – only three numbers are required.
“Yet
theories about multiverses, et cetera, have all kinds of parameters,” says
Turok. “The theories are just way more complicated than the phenomena.”
So what
will Convergence do differently? First, it will bring together all fields that
are giving interesting clues, including experiment and theory. Second, invitees
are strongly encouraged to come with an open mind. “Convergence,” says Turok,
“aims to bring theorists and experimentalists together in humility –
acknowledging that other methods haven’t panned out. We need to say in an
honest way where we’re stuck.”
That sounded good, so I followed the conference blog for a summary of what was
happening. Despite the high expectations for the conference, apparently nothing
new surfaced there. The final post, summarizing the closing panel, stated that
the same underlying questions motivated everyone: “What are we missing? What
puzzles remain?” This was taken in a positive way, meaning that everyone had
the right attitude. However, I first heard these questions with negative
connotations eleven years ago, as I reported here. Physicists had no answers
then, and they still have none.
The word “exciting” and its variations appear
eight times in the two-page closing panel summary. Everybody agreed that the
questions, of which there are plenty, are more exciting than answers, of which
there are none, in spite of the fact that some of the questions have gone
unanswered for decades. That sounds more depressing than exciting to me. Still,
Physics World reports that most of
the participants thought the conference was a success, allowing researchers
from different branches of physics to meet and share ideas.
Those folks could find many of the answers in
this blog, of course. However, the last person a physicist wants to hear from
is a retired electrical engineer, as I reported in the very first post of this blog, almost exactly
one year ago.