Thursday, June 9, 2005

Why no new Einstein?

My guess is that this freely available web page contains the announced new text by Lee Smolin that was published in the newest issue of Physics Today and mentioned on the blog Not Even Wrong (where Peter Woit displays his harmony with Lee). While I agree with many of Smolin's points about the nature of Einstein's discoveries and with his call for independence, it is hard to subscribe to the policies he proposes or even the topics that should be supported by various agencies and "Einstein fellowships". Let me start with Einstein, his approach, and his flaws.

Einstein - a maverick and a mainstream physicist

First of all, it is indeed true that , the amazing guy who has totally revolutionized our picture of physics at least twice in his life, was a rather average person in many respects. Minkowski, his high school high teacher, certainly had a reason to call Einstein "the lazy dog". Einstein's poetry was mediocre and his violin skills were so-so.

Later in his life, Einstein showed his inability to understand the new conceptual breakthroughs, especially those based on quantum mechanics. Because I believe that quantum mechanics represents the single most profound revolution in the 20th century physics, Einstein's misunderstanding of its inevitability was a pretty serious imperfection. Nevertheless, Einstein was able to transform his flawed opinions about quantum mechanics into something that led to great insights (about the entanglement) later. On the other hand, if Einstein were only a person who disliked quantum mechanics, we would not be celebrating him as the ultimate intellectual superhero today.

The year 1905 was Einstein's miraculous year. But Einstein would also fail to be a full Einstein if he did not find anything else later. Fortunately he did. In 1915-1916 he finished general relativity. The observations of bending light made Einstein an international celebrity in 1919. Einstein had to struggle for 10 years before the light of GR emerged in front of his eyes. During the long, exciting, and frustrating period he had obviously made a lot of errors, and he needed a help from Marcel Grossmann. It is conceivable that Einstein could have problems to get a decent job today if he needed 10 years to write
  • "S = int sqrt(g) R d4x / (16 pi G)"
or something like that. ;-) Yes, one may think that Einstein was a bit lucky, too. But what I would like to emphasize is the following:
  • It is very hard to imagine that one can artificially construct or social-engineer a new Einstein.
I will discuss this point in detail later. There is one more thing about Einstein that Lee does not seem to appreciate:
  • Einstein was not a classical crackpot.
What do I mean? Although Einstein came from a completely different environment than the mainstream scientists, he was more than familiar with all existing fundamental physics of his time. He did not claim it was wrong. In fact, he viewed special relativity as a small update of Newton's and Maxwell's insights.

His interpretation of some of the key aspects of Maxwell's theory were actually more conservative than the mainstream, and he agreed with some of the big visions made by the leading physicists. He appreciated the principle of relativity - something that other famous physicists would also agree with, but they underestimated its importance. Einstein was also impressed with Lorentz's results about the vacuum Maxwell's equations. Lorentz was a well-established physicist and Einstein understood very well that Lorentz's re-interpretation of Maxwell's equation, with one electric and one magnetic vector in the vacuum only, meant that aether was dead. Unlike Lorentz, Einstein also realized that this suggests that the equivalence of different reference frames should hold even for electromagnetic phenomena - even if we try to measure the speed of light. The latter should therefore be universal.

We know the final wisdom: all reference frames are equally suitable for formulating the physical laws - especially Luboš Motl's reference frame :-). If you have a feeling that this frame plays a unique role in the previous sentence, note that all other bloggers are also unique, like everyone else. :-)

Einstein was able to put all these things together. He figured out that one must sacrifice an assumption - that the simultaneity of events is absolute - that the people before 1905 considered so obvious that they did not even know that it could be questioned. They did not have the idea to ask the question whether the assumption was right. Today, we know that it can be questioned, it should be questioned, and it is in fact incorrect. The theory that makes the simultaneity relative is correct and it nicely agrees with the previous theory in the non-relativistic limit.




Real Einstein vs. New Einstein

Some of the signs of a "new Einstein" proposed by Lee Smolin are of very different nature. Lee wants to promote the people who disagree with some well-tested principles that the physicists have studied for decades. For example, physicists have asked since 1926 whether the probabilistic interpretation of quantum mechanics is inevitable. Hundreds of people have worked on this issue for decades, and the answer is essentially Yes, it is inevitable. It's not surprising that those who still want to replace quantum mechanics by a classical theory or something very similar are viewed as crackpots by most of the physics professionals. I also think that they are crackpots and I have myself made some attempts to embed quantum mechanics into a classical/deterministic framework - the last attempt was made before the 17th birthday.

The situation with the foundations of quantum mechanics in 2005 is very different from the position of young Einstein in 1905: he only questioned things that were never really discussed, not things that the leaders of physics have known to be provably wrong for decades.

Groupthink vs. independence

Lee says that it is wrong if everyone mimics the "groupthink". Well, my readers know very well that I don't have to prove that I am in agreement with Lee on this point: the acts are more important than the words and they show what they show. But what Lee does not appreciate is that
  • the "group" with its "groupthink" does not have to be always wrong; in fact, it is often correct, and it is even more likely to be correct if these results are supported by thousands of quantitative and often precise papers and experiments
  • even an independent person can actually find out that his or her important questions have already been discussed in literature - either by other independent scientists or by dependent scientists ;-) - and they have been answered in one way or another

Undoubtedly, Lee is correct that those who follow the well-established directions in physics are more likely to be the same people who care about their career; the same people who publish regularly with a rather uniform inflow of citations; and the same people who are more likely to miss some essential points that require a bigger deviation from the "normal science" and that can be preventing us from making another revolution. But what Lee does not want to see is that these people are needed for science of the modern type, and they're often doing a great work. Science has simply become a professional field of human activity which means that there are obviously people who treat science just like another job.

Einstein used to say that the forest could not grow if these career-oriented colleagues were the only plants in it, but on the other hand, modern science would also be in a much worse shape today if these people did not exist - which is why I am mostly grateful to all of them.

But Lee Smolin is definitely not right when he suggests that an original thinker can be identified by a small number of citations and papers. These are definitely neither sufficient nor necessary conditions. And it would be a pretty weird policy if institutions were considering these characteristics as advantages. Such a policy would attract many people who can simply behave as potential geniuses and match Lee's requirement. And most of these people would have nothing to do with deep thoughts.

Lee's proposal is a textbook example of a cargo cult science: some primitive tribes in the Pacific ocean have a magician with wooden earphones - he's the dispatcher - and the whole tribe expects the U.S. airplanes to land once again just like they did during the World War II when they brought a lot of good stuff to the island. There is a problem however: the airplanes don't land. In the same way, Lee identifies some characteristics of Einstein such as his independence and a small number of routine papers (the wooden earphones), and he believes that if these characteristics (earphones) are prescribed as the standard, we will be surrounded by new Einsteins. But we won't (the airplanes won't land) because in both cases, Lee (or the tribes) misunderstand what is the cause and what is the effect. A dispatcher is just a consequence of the U.S. decision to send planes to the island; Einstein's independence is one of his defining personal properties. But the opposite implications don't work: the earphones can't create airplanes, and artificially created symptoms of independence can't lead to a new special relativity.

No doubt, those who mostly ignore their career and who try to solve important problems that don't have to overlap with the problems defined by the mainstream science are taking a risk. Not only they're taking a risk: it must be so that such a behavior is risky, otherwise the system could not work efficiently. Hiring an original thinker is a risk for the employer, too - although a smaller one unless the job is permanent - and the results of such a risk partly depend on the luck.

General relativity did not work for almost 10 years. Moreover, there were many people who may have been as smart as Einstein but who were just not lucky enough to be born at the right time. One should be suspicious about the French who allegedly give tenure to "original thinkers", as Lee describes. I am not sure whether the French economy can afford such things. The very concept of tenure may be questioned, but in some particular cases it is obviously irrational.

Once again: the environment that gave us Einstein was surprising, and you cannot arrange such surprises. The next revolution in physics comparable to Einstein's contributions could start at a celebrated U.S. university, another Swiss patent office, or perhaps at one of the currently underestimated schools in Germany or elsewhere in Europe (which I currently find relatively likely). But if such a revolution is a real shocker, be sure that the planning and the statistical analysis how the new Einstein should look like will mostly fail. The new Einstein can have different hair and perhaps even gender than the old one. It can be Zweistein, Goldstein, Silverstein or even Dzhugashvilli.

While Lee Smolin says that the young people should not be forced to follow senior leaders, he proposes the following highly original and independent topics that should be supported:

  • loop quantum gravity
  • questioning the foundations of quantum mechanics
  • testing high-energy predictions of alternative theories
  • ...

I am not sure whether you are, Lee, just joking, but it simply does not sound terribly serious if someone writes that the young scientists should become more original, but at the same time, he tells them that they should be working exactly on Lee's favorite problems.

As everyone who reads this blog already understands, the question whether the basic probabilistic structure of quantum mechanics is a good framework may have been a question at the frontier of physics around 1927, but it is definitely not an interesting question for current research in 2005. Someone who wants to reject these foundations of quantum mechanics is not a new Einstein: he or she is an old Einstein - but an old Einstein that only has Einstein's flaws and failures but not his virtues and victories. The only truly open questions about the interpretation of quantum mechanics are those that also require us to understand dynamics of quantum gravity properly.

As far as I can say, loop quantum gravity is a flawed attempt to revive the old idea of aether - which, unlike the original notion of electromagnetic aether from the 19th century, does not work even in theory - and doubly special relativity has never been reliably related to loop quantum gravity and there are hundreds of independent reasons why doubly special relativity is irrelevant for the real world, too.

More generally: LQG, DSR, antiQM etc. are not new original ideas. They are most likely incorrect ideas that have been around for decades. If someone expects that they will slowly be accepted and such a slow process is analogous to Einstein's revolution, it is naive. This is not how physics works. The real Einstein got his idea how to put special relativity together, sent the paper to Annalen der Physik. Within a few weeks, Max Planck read the article, he immediately recognized that it was correct, and so he published it. Special relativity was instantly accepted by virtually all leading mainstream physicists as the correct theory of kinematics and dynamics at speeds comparable to the speed of light. And the penetration rate today would be even faster because of the internet and other modern media.

This history has absolutely nothing to do with the painful developments of LQG, DSR, antiQM, or similar proposals, and only a person who believes his or her infinite importance can think that the situation is analogous to the history of special relativity. Incidentally, the proponents of the "scientific consensus" (about the global climate, for example) have a very similar idea to Lee who otherwise promotes "independence": they also think that one does not have to publish any shocking paper that really and instantly answers a question; they believe that it is enough to keep on publishing ambiguous and confusing papers for many years until others lose their patience, accept these statements, and contribute to the "scientific consensus".

No, this is not how good science works. Lee's papers are very clearly readable for me, so you can be sure that once he correctly and convincingly solves a big problem in quantum gravity, I will understand the framework of his solution one day after he submits it and the details will follow a week later. And tens of others will understand it, too. There is no reason to wait for 10 years.

Concerning Lee's comments about string theory: I believe that they're misled, too. It is almost guaranteed that a better conceptual insight about physics beyond the Standard Model and about quantum gravity will have to be a better understanding of string/M-theory although this new understanding may be drastically different from the methods that are dominant in string theory today, and, indeed, some of the insights proposed after the second revolution in the mid 1990s may be rejected.

However, string/M-theory has simply become a part of the standard theoretical cannon. Hiring people who are ignorant about string theory as the "new Einsteins" who search for theoretical (not phenomenological) concepts behind the Standard Model would be equivalent to the search for Einstein in 1905 among those patent clerks who didn't know Maxwell's equations.

Summary

So let me propose to avoid Lee's experiments. The intellectual independence cannot be defined by regulations. If independence is prescribed as a law or a hiring criterion, then it's no longer independence. On the other hand, if there are some really independent people around, they will do their best to find their way through the system that - everyone agrees - tends to prefer "groupthink". But independence is not a sufficient condition for a success. Some independent people have a chance to win their battle; others may lose. You must know that big progress in physics is less guaranteed than baking bread. All of us may be unlucky and the new breakthrough may have to wait for the 22nd century.

If the mavericks are not doing their job because of their careers, be sure that they may disappear if things don't work correctly for them. But this is how the things must look like if there is any order in the world. And finally, let me encourage everyone to be a bit independent.

See also: Why no new Einstein II