Follow-Ups to two recent postings:
Michael Duff has written a letter to New Scientist complaining about their recent editorial Physics’ greatest endeavour is grinding to a halt. Duff begins by claiming:
History has shown that rapid confirmation by experiment is a poor guide to the eventual value of a physical theory
but backs this up in a rather bizarre way. You might think he would list some physical theories whose experimental confirmation took awhile, instead he lists various theoretical ideas that have been around for a long time, still haven’t been experimentally confirmed, although lots of people are still working on them. Evidently for Duff the value of a physical theory is how many people are working on it (he also points out that about 500 people go to Strings 200X), not whether there is any experimental evidence for it. The examples he gives range from cases where there is zero experimental evidence, and probably never will be any (extra dimensions, supersymmetry) to ones that it is very plausible we will soon see evidence of (Higgs boson, gravitational waves) to ones that arguably we already have some evidence for (cosmological constant).
He notes that gravitational waves were predicted in 1916 and have yet to be confirmed, that string theory is more ambitious than GR so it should take longer to confirm, and that one should only really start counting in 1995, when M-theory came along. So I guess his prediction is that by 2074, we still won’t yet be anywhere near confirming string theory. Like many string theorists, he make highly tendentious claims about the relation of the standard model to experiment, writing:
decades [were] required to knock the standard model into a shape that could be confirmed by experiment
I assume he’s not talking about the QCD part of the standard model, which was born in 1973, already making verifiable predictions, and within ten years had accumulated a huge amount of evidence in its favor. The electroweak theory was first written down by Weinberg and Salam in 1967, and by ten years later the evidence for it was overwhelming. I suppose you could try and argue that the history of attempts to put together the standard model go back to Glashow in 1960 or Yang-Mills in 1954. Even using 1954, it was 19 years later that the full standard model was in place with a lot of experimental evidence already there and more pouring in. And that period would quite likely have been shorter if most of the theory community hadn’t given up on QFT and been working on the bootstrap, dual models or string theory during that time. In the case of string theory, taking Veneziano in 1968 as a starting point, nearly 4 decades later there is not a glimmer of a piece of experimental evidence for string theory. Comparing the history of the standard model to the history of string theory is just absurd.
On another recent topic, the New York Times finally today carried an obituary for Raoul Bott.