Symmetry magazine today published an article on Falsifiability and physics, yet another in the genre of defense of current HEP theory against its critics. As usual, only defenders of the status quo are quoted, the critics remain unnamed and their actual arguments ignored. I don’t completely understand this journalism thing, but if you are writing about a controversy, aren’t you supposed to contact people on both sides?
The problems with this article begin with the misleading subtitle: “Can a theory that isn’t completely testable still be useful to physics?” The problem here is not theories that aren’t “completely testable”, but theories that aren’t testable at all, that make no testable predictions at all.
The article starts out by discussing Popper and the supposed “falsifiability” criterion for what is and isn’t science, leading up to:
But where does this falsifiability requirement leave certain areas of theoretical physics? String theory, for example, involves physics on extremely small length scales unreachable by any foreseeable experiment. Cosmic inflation, a theory that explains much about the properties of the observable universe, may itself be untestable through direct observations. Some critics believe these theories are unfalsifiable and, for that reason, are of dubious scientific value.
Who are these “some critics”? Where do they say that the reason there is a problem with string theory is “unfalsifiability”? For the case of one critic I’m pretty familiar with, chapter 14 of his book is all about how “falsifiability” is not something that can be used to decide what is science and what isn’t.
We’re then told that:
At the same time, many physicists align with philosophers of science who identified flaws in Popper’s model, saying falsification is most useful in identifying blatant pseudoscience (the flat-Earth hypothesis, again) but relatively unimportant for judging theories growing out of established paradigms in science.
Unclear who “many physicists” are, who the “philosophers of science” are, and what flaw in Popper is being referred to.
In an odd move, the article then turns to the topic of SUSY, where the problem isn’t that well-advertised SUSY models (with electroweak scale SUSY breaking solving the “naturalness” problem) aren’t falsifiable, it’s that the LHC has falsified them. As usual in science, if your model gets falsified, instead of giving up and doing something else you can change your model to something less desirable that hasn’t been falsified (SUSY models with symmetry broken at higher energy scales) and keep on going. This is though what philosophers of science call a “degenerating research program”, which is not a good thing.
There’s more in the rest of the article, but actual critics remain invisible and their actual arguments unaddressed.
Update: Will Kinney has some appropriate comments.