- Peter Orland has a new blog, Ensnared in Vacuum, where he’s writing about some non-perturbative QFT questions.
- Physics Today this month has book reviews of two books about theology and the multiverse (one of which I wrote about here). There was a time when I would have thought that discussions of theology wouldn’t be what Physics Today covers, but evidently that’s no longer the case.
- On a related topic, Kate Becker at The Nature of Reality has an article entitled Does Science Need Falsifiability? It’s about the campaign by physicists like Sean Carroll and Lenny Susskind against the Popperazi who keep pointing out that giving up on falsifiability puts physics in danger of becoming, well, theology. Frank Wilczek has a very sensible take on the subject:
“I think falsifiability is not a perfect criterion, but it’s much less pernicious than what’s being served up by the ‘post-empirical’ faction,” says Frank Wilczek, a physicist at MIT. “Falsifiability is too impatient, in some sense,” putting immediate demands on theories that are not yet mature enough to meet them. “It’s an important discipline, but if it is applied too rigorously and too early, it can be stifling.”
On Twitter, the usually mild-mannered Wilczek makes clear his feeling about this
Not often I refer to a “pernicious” “faction”, but appropriate here.
Mysteriously, he has a new website, for a company “Wolfcub Vision, Inc”.
- Frank Close has a new book out, Half-Life, which is essentially a biography of the physicist Bruno Pontecorvo. It’s also a gripping spy story, investigating the question of exactly why Pontecorvo fled with his family to the Soviet Union in 1950. There’s no smoking gun found, but all the evidence Close lays out makes the case that it is quite likely that Pontecorvo had been spying for the Soviets, fleeing when warned that he was in danger of being exposed.
Freeman Dyson has a much better review of the book in the New York Review of Books than I could ever write. He argues that Pontecorvo made a mistake by fleeing to enforced isolation in Russia, that in the worst case if caught he would have spent a few years in jail, then could have resumed his career. That things would go this way would not however have been clear to Pontecorvo: the Rosenbergs were arrested just before he fled, and things didn’t work out so well for them.
Besides the fascinating spy story, there’s also a lot of history of nuclear physics during the 30s, 40s and 50s, much of which I wasn’t aware of, as well as quite a bit about Pontecorvo’s later work on neutrinos. If you’re interested in the history of 20th century physics, this is something you’ll find well worth reading.
Update: For another new book, Steven Weinberg’s To Explain the World, I fear that I don’t have the time to read it and write a review. However, here are two interesting reviews, pro and con.
Update: For two hints about “Wolfcub Vision”, a commenter points out that Wolf cub=Wilczek in Polish, and a correspondent points me here.
Update: David Mumford has a posting Is it Art? at his blog, motivated by my friend Dan Rockmore’s equations project. An article about the recent panel discussion of this at Yale is here.
Hi Peter,
Thanks for letting people know.
I’m confused, maybe ignorant, but what is Wilczek implying?
My guess is that Wilczek is just expressing the same opinion as most scientists hold towards those who, like Carroll and Dawid for instance, are trying to claim that their favored theories are still science even if unfalsifiable: they’re a minority (a “faction”) and they’re doing something blameworthy (“pernicious”).
A bit off-topic but since the post is also about history of physics: I do not know if you have heard of that, but in Italy there is some “official announcement” (from a prosecutor – “procuratore” in Italian) that Majorana was alive after he disappeared, and was in Venezuela between 1955 and 1959. The elements do not seem so convincing at first sight (a postcard, a “physionometric” analysis of a picture) but enough for a prosecutor to make this claim.
Wilczek means in Polish a wolf cub…
So, the falsifiability argument is really about theories with different confidence intervals. Tight confidence intervals tend to come from the ability to do repeated, controlled experiments. There are plenty of interesting questions out there where you might want to develop theories but have very limited data and no ability to do repeated, controlled experiments. Climate studies, macro-economics, Planck-scale physics and cosmology are among them. It’s fine to develop theories (or really hypotheses) in these disciplines that explain whatever data you do have, but the extreme limitations of such an enterprise need to be understood from the beginning. Lumping activities with wildly varying experimental confidence intervals and ability to do controlled experiments together all as “doing science” is where the trouble begins. They are really different categories of activities. The famous puzzle of the man hanging from a noose in his house with a puddle of water under him is a good example. N=1; can’t do the experiment again. Plenty of interesting hypotheses. The smartest guy in the room comes up with the ice block hypothesis. It’s elegant and explains the limited facts. Is it “true”? We will never know. Is it worth working on more elegant explanations for these kinds of puzzles? That is a matter of personal taste and available resources. Perhaps the work itself will help techniques that lead to solutions to other puzzles with more verifiable solutions.
Mesa,
I don’t think that’s the problem here, what you refer to is a conventional well-understood issue that never led to people arguing that falsifiability should be abandoned. The motivation of people like Carroll, Susskind, Dawid who are now arguing against falsifiability is very clear: they have specific untestable theories that they want to promote, of exactly the sort of thing that conventionally are not considered to be science, and that Popper’s criterion was specifically designed to rule out as pseudo-science (multiverse explanations of the arrow of time for Carroll, multiverse explanation of why string theory says nothing about particle physics for Susskind, lack of any predictions by string theory for Dawid).
Most physicists immediately see where this kind of argument leads and want nothing to do with it. What’s amazing is how much traction those pushing this have gotten despite this.
Well Wilzcek has an office at Arizona State University’s biophysics floor right down the hall from mine, so that should give a hint as to what he’s been up to. Maybe if I work up the courage I’ll ask him, I see him wandering about from time to time.
I must object to Mesa’s implied inclusion of climatologists (and even economists) in Carroll’s looking glass world. I suggest he review what empiricism means.
PW
I think we a largely in agreement here. I am just pointing out that there are large swaths of this activity going on in other spheres as well, and these activities should be regarded as different in type from normal science. Whether they are worth doing or not can be debated, but it should be clear they shouldn’t be the main line of inquiry. To me, lack of falsifiability is the same thing as small number of observations . Non repeatable small number of observation problems can’t really be solved with any confidence, just discussed. However, that may not mean that they are not worth discussing.
paddy
I lumped together a group of activities where the data was limited (one way for data to be limited is to have only one history, ie small number of observations) and controlled experiments were not possible. Both climate science and macro-economics fit that description exactly, as well being highly complex systems too boot. I did not claim there was no data. One way to easily identify these types of fields is that there is a lot of emotional debate about fundamental issues, even among skilled practitioners. Again, macro-economics and climatology fit that description exactly. The debates then turn to arguments over extremely simplistic models and politics.
” He argues that […] in the worst case if caught he would have spent a few years in jail, then could have resumed his career. That things would go this way would not however have been clear to Pontecorvo: the Rosenbergs were arrested just before he fled, and things didn’t work out so well for them.”
As the Rosenbergs were executed after Pontecorvo fled to Russia, it is difficult to understand how their execution could have effected his decision to flee.
Visitor,
My point was that Pontecorvo had no reason to believe that the worst-case scenario if he stayed was a few years in prison for him. The later execution of Rosenberg and his wife shows that he quite rationally could have been worried about this. I don’t know if it was known soon after Rosenberg’s arrest that he would be charged with crimes carrying a death penalty, but it’s possible that was the case.
The ‘con’ review of Weinberg’s new book erroneously states (unfortunately, before the pay wall where it can be seen):
“As his active involvement in research declined, he has become a prolific contributor to what’s called the “public understanding of science” ”
The reviewer clearly has little or no idea of Weinberg’s recent research. Off the cuff, in the last 10 years Weinberg has made important research contributions to cosmology (and in the process written what could be the standard monograph in the subject), the interpretation of quantum mechanics, and particle physics (conformal symmetry). Indeed, in the last year or so he even pointed out that contrary to reasoning of one of his illustrious former colleagues, accepted by almost everyone, tetraquark states may indeed be ‘visible at leading order in 1/N. I would guess > 99% of theorists would be happy to have Weinberg’s research in the last ten years as their career achievement!
Not that Weinberg really needs any defending here. We know he is in the same league as Bethe when it comes to research longevity. What boggles the mind is that a journalist could have the nerve to make such a judgement. In Weinberg’s case it may have more than a little to do with the fact he seems, according to the journalist, to critically assess the received wisdom of Enlightenment 101!
Dirac sometimes suffers similarly, with the ill-informed jibe ‘he did little after the 1930s’ or something to that effect.
“Our current best understanding of science shows no evidence for a multiverse, so anyone who wants to posit one needs to come up with some significant evidence for one, experimental or theoretical, and I haven’t seen that happening. … the question of multiple universes is well worth ignoring…”
It seems to me that significant theoretical arguments for the multiverse do exist, which is why you aren’t ignoring them.
Too distinguished,
I’ll just point out that you changed my “significant evidence” to “significant theoretical arguments” which is a different thing…
Frequently repeated is not the same thing as significant. Outside of a fairly small enclave (largely consisting of those with a vested interest), these arguments are seen as a total joke.