What do you do if you are a second-rate theorist but wannabe famous? The answer used to be: tough, try your luck as a rock musician instead. These days it is not so simple. Several factors have come together:
(1) the idea that it is only fair that everyone should be allowed to delay their entry to the workforce by going to university;
(2) the need for a huge increase in the number of researchers to teach all these undergraduates;
(3) resulting in a dramatic drop in the average competence of researchers;
(4) the difficulty of funding their research, and increasing pressure on them to spend time getting their own funding;
The final upshot is a dramatic increase in academic advertising of research. Fifty years ago advertising meant giving a low-key seminar. If the audience was somewhere like the Cavendish laboratory in Cambridge, then this was something to be approached with considerable trepidation. The Cavendish audience took the view that the kindest thing you could do to someone talking nonsense was to point out the flaws. That way the speaker would not need to waste any more time proceeding up a blind alley. Speakers were frequently reduced to tears.
These days it is considered bad form to ask anything the speaker anything unless it is done in an oleaginous Parkinsonian way which carries no risk of embarrassing him (or her).
But advertising of academic work has now come much closer to advertising soap flakes on television. Take for example, a series of hopeless papers by Holger Nielsen at the Niels Bohr Institute in Copenhagen University.
I strongly advise against reading them. They are unbelievably bad. The first I have been able to find dates from about three years ago hep-ph/0612032v2 at arxiv.org. The latest seems to be gen-ph/0802.2991v2 from July 2008.
The basic idea is that a rewrite of the laws of physics so that the future affects the past would be the only explanation for an otherwise unexplained breakdown of the Large Hadron Collider. This seems to me so batty as to need no further comment.
I have to admit that I am prejudiced, because the work seems to have its genesis in string theory. String theory, known then as supersymmetry, was just getting going in the applied math department when I was an undergraduate at Cambridge in the late 1960s. The objective was noble: to reconcile Einstein gravity and quantum field theory (QFT). This was an important objective. It is little appreciated outside the relatively small number of people working in fundamental physics that physics is plagued with contradictions. Something like the famous Gödel results in maths, but much, much worse.
The Gödel results just show that various things it would be nice to have, like simple proofs of the consistency of maths, are unavailable. The physics results show that the existing theories contradict themselves and each other. The worst of these problems is the contradiction between gravity and QFT. Roughly speaking, QFT shows that empty space has infinite energy. That might not matter, you could “subtract it off”, except that energy has mass and so attracts gravitationally. But we do not observe things being attracted to empty space.
A neat theoretical approach in the first half of the twentieth century had been to regard forces as related to symmetries, so mathematicians started looking for large “symmetry groups” or “supersymmetries” which could combine gravity with the other forces in an elegant way and get rid of this contradiction.
This approach to science, the “laws must be elegant” approach, has never worked. It is only with hindsight that laws painstakingly found by other means have been reformulated as elegant maths. Maths seems to have too much freedom. Simply postulating a fundamental physical law and saying let us see what happens if this is true has never got anyone anywhere unless the speculations were closely tied to real data. [Postulating a new fundamental law is quite different from expressing an existing law in a more elegant and general mathematical form. That is often quite productive.]
Postulating supersymmetry groups certainly proved barren. String theory was repeatedly disproved. The first problem was that it predicted that protons decay. Of course, they don’t. But the prediction was not that they decay over a few seconds or hours, but that they decay over a time far, far longer than the lifetime of the universe, so it might not seem too serious.
But the prediction was of random decay – just like ordinary radioactive decay. So if you watch a single proton, then the chance of its decaying over a few billion years is negligible. But you can do better than that by watching a cupful of ordinary matter, which contains a simply huge number of protons. The calculations suggested a few kilos of protons would provide a wealth of collisions over a few months. Before long someone had run the experiment and showed there were none.
At this point the real problem with the theory became apparent. It was infinitely adjustable. Having no particular basis in experiment, it was constrained only by elegance and any competent theorist, knowing what he needed (a longer proton lifetime), could easily give the theory the required tweak and claim it was even more elegant. A new version soon became available predicting a lifetime a thousand times longer. The experimenters were delighted. A bigger, more expensive, more prestigious experiment was called for, and a few years later had again disproved the theory.
Meanwhile, a much more intractable problem was that the theory predicted a vast number of “fundamental” particles which simply did not exist. They were initially known as “sparticles” for super-particles, arising from supersymmetries.
That might have been the death knell of the theory, but for the fact that gravity itself was by now in deep trouble, courtesy of an innocuous-sounding piece of work, known as “flat rotation curves”. It turned out that if you started looking carefully at the motion of stars around galaxies, or of galaxies around each other, then they moved much too fast, as if the gravitational attraction between them was much stronger than the famous Einstein theory predicted.
Unfortunately, the secular scientists had canonized Einstein. The popular piety was that you rated physics professors in three classes (rather like undergraduate degrees) I, II and III. But there was also a class Zero, with Einstein as the only holder. That made him a kind of secular God, the person every theorist secretly wanted to join in class Zero, so it was impossible that his theory could be wrong.
The answer was “dark matter”. At first sight, that is not so implausible, maybe there is lots of invisible stuff out there in the heavens which is pulling the galaxies along at a rapid clip. But more elaborate calculations showed that is not the case. First this invisible attractant would have to be distributed in bizarrely complicated patterns to fit the data. Second, and much worse, even more elaborate calculations soon showed that it would have to be “exotic”, having quite different properties from the ordinary matter here on earth which we thought was universal.
One day a string theorist fell to chatting to a dark matter theorist in a coffee room. Each realized that he could solve the other’s problem without actually solving it. All those non-existent exotic particles did exist after all, but way out in the distant universe. What were they doing there? Pulling the galaxies the way we observe. Yippee!
So two bad theories became entrenched. The details were never worked out. The dark matter types gave up predicting or explaining troublesome data. Anything that was observed was just taken to be some exotic particles whose only observable effect was the aberration in their results. The string theory types gave up worrying about the non-existence of the exotic particles, because they had the comfort of knowing that they did exist, albeit too far away ever to be checked against their theory.
Of course, Nielsen’s skill was to reckon that teething troubles at the Large Hadron Collider were fairly likely, and to start publishing his nonsensical papers before the switch-on. Unfortunately for him, he was gazumped at the first switch-on by even sillier, but more news worthy, tales of tiny black holes which would eat us all up.
But the machine soon fell victim to technical problems and had to be switched off for repair, so he had another chance. In the run-up to the new switch-on next month he has evidently been busy. Plenty of gullible science journalists are lapping it up. After a good run on the New York Times and Telegraph earlier this week, Channel 4 News picked it up on Wednesday evening.
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