Today, the winner of the $3 million 2014 Milner Prize (see candidates) will be announced in San Francisco along with five winners of the $3 million Milner-and-few-pals Award in Life Sciences (I hope that I remembered the official name of the honor exactly). One $3 million prize for a psychic (no kidding) will be decided in January. Watch the news.A week ago, Nima Arkani-Hamed gave a talk on a one-day symposium in Stony Brook; click here if the HTML5 video tag below doesn't work for you.
His talk about the exotic methods to calculate the scattering amplitudes in gauge theory (and the whole symposium) was dedicated to David Kosower, Lance Dixon, and Zvi Bern who recently received the 2014 Sakurai Prize.
Aside from interesting comments on the internal structure of the amplitudes, the integrability that is being obscured by the local-and-unitary description based on Feynman diagrams, and the interesting creative confrontation between the S-matrix-like and Feynman-diagram-based techniques, Nima would say interesting things about the sociology of physics and especially the different personalities of physicists.
These sociological comments appear close to the beginning; and around 21:00.
To make the story short, even good physicists are divided to prophets and non-prophets. I think that Nima is using the word "ideologue" as a synononym for a "prophet". Kosower, Zvi, and Bern are also being praised for having been able to work on topics that were not really fashionable. Some authors of junk popular books use the word "seer" and it means pretty much the same thing, although at a more vulgar and obscene level.
A difference is that Nima views the "prophet" label as a negative one. These people are overpriced, he thinks, and they are often given credit for making vague prophesies that turn out to be right "in some sense" even though some degree of agreement is almost guaranteed to materialize and very different people have done the hard work to decide what is exactly true and what is not true and why.
Kosower, Bern, and Dixon are praised as the non-prophets by Nima; Nima himself degrades himself into a prophet. In fact, he is a serial ideologue who is ready to become an enthusiastic supporter of today's ideology while instantly abandoning yesterday's ideology. On the other hand, the really smart people don't need any ideology – they just adopt ideas from all sides and create something neat out of them, Nima explains. Needless to say, Nima is displaying some (cute but partially staged) modesty and apparent masochism by these comments; he is an excessively good worker who is also using ideas from all directions, regardless of the origin.
I would like to emphasize that this separation of the physics community wasn't invented by Nima Arkani-Hamed (or Lee Smolin). I've been aware of a similar one for 25 years – since my first reading of Albert Einstein's 1918 speech celebrating Max Planck's 60th birthday that was included in "Mein Weltbild", a book whose Czech translation I liked to re-read as a teenager.
In the temple of science are many mansions, and various indeed are they that dwell therein and the motives that have led them thither. Many take to science out of a joyful sense of superior intellectual power; science is their own special sport to which they look for vivid experience and the satisfaction of ambition; many others are to be found in the temple who have offered the products of their brains on this altar for purely utilitarian purposes. Were an angel of the Lord to come and drive all the people belonging to these two categories out of the temple, the assemblage would be seriously depleted, but there would still be some men, of both present and past times, left inside. Our Planck is one of them, and that is why we love him.You see that it's not quite the same thing but it's related. Einstein divided the temple of science to profit-seekers (or utilitarians) and ego-builders (or athletes) on one side and monks (or missionaries) on the other side. Max Planck was included into the rare latter category by Einstein. Despite Einstein's stellar moral credentials in the public, I actually find it plausible today that Einstein himself might have been a representative of the former category as the Einstein and Eddington movie suggested. He might have been an utilitarian, not a monk (which I used to believe to be an accurate label for Einstein 25 years ago).
I am quite aware that we have just now light-heartedly expelled in imagination many excellent men who are largely, perhaps chiefly, responsible for the building of the temple of science; and in many cases our angel would find it a pretty ticklish job to decide. But of one thing I feel sure: if the types we have just expelled were the only types there were, the temple would never have come to be, any more than a forest can grow which consists of nothing but creepers. For these people any sphere of human activity will do, if it comes to a point; whether they become engineers, officers, tradesmen, or scientists depends on circumstances. Now let us have another look at those who have found favor with the angel. Most of them are somewhat odd, uncommunicative, solitary fellows, really less like each other, in spite of these common characteristics, than the hosts of the rejected. What has brought them to the temple? That is a difficult question and no single answer will cover it. To begin with, I believe with Schopenhauer that one of the strongest motives that leads men to art and science is escape from everyday life with its painful crudity and hopeless dreariness, from the fetters of one's own ever shifting desires. A finely tempered nature longs to escape from personal life into the world of objective perception and thought; this desire may be compared with the townsman's irresistible longing to escape from his noisy, cramped surroundings into the silence of high mountains, where the eye ranges freely through the still, pure air and fondly traces out the restful contours apparently built for eternity. With this negative motive there goes a positive one.
But let's gradually return to the modern separation to prophets and non-prophets. While the prophets are analogous to Einstein's monks when it comes to their spiritual motives, it is the non-prophets who may be closer to Einstein's description of the monks when it comes to the silence and modesty. So a bit paradoxical transformation of the two groups has taken place; it's the prophets (formerly monks) who are good at exciting emotions and P.R. these days and the engineer-like hard workers are the modest ones. ;-)
I don't want to make this discussion completely chaotic so let's return to Nima's modern separation of the two castes of physicists completely. Which group is "better"? Well, I think that both groups – and groups in between as well as completely different groups – are important for the health of science. Lots of detailed if not "microscopic" work has to be done for the big-picture or at least "macroscopic" skeleton to be robust. And the microscopic work may often grow to something grand.
On the other hand, if Nima were suggesting that the "ideological", big-picture thinking may be completely removed from science, I would strongly disagree. Even if we agree that science is not "entirely" about the big-picture questions only, it is "also" about them. The big-picture thinking is needed to be aware of the relative importance of different kinds of the microscopic work, too. It's needed for the bulk of researchers not to be caught in some minor technicalities while big questions and discoveries in different research directions remain neglected.
So the non-prophet researchers often end up doing many important results but this fact doesn't make their attitude superior because there are many non-prophet researchers who aren't that happy. In some sense, I do think that the importance of the research separated from the big picture is a matter of chance. (It may be non-PC these days but I still find it important to point out that I still consider Lance Dixon's work between 1985 and 1991 on orbifolds and related questions in string theory – including the monstrous moonshine – to be more important than all his later work on amplitudes combined. And I know some profound researchers who agree with me.) Moreover, the big-picture interpretation of some results is often a matter of a clear thinking. Someone doesn't see what some partial technical results actually mean, what are their (more) far-reaching implications, but someone else does see it and it's important to know it if it is true – or at least "somewhat vaguely true".
The really dangerous trap of the "ideological" approach to science – and Nima is obviously aware of it – is the ability of the ideological prejudices to remove one's impartiality. One may invent rationalizations for the decision to ignore some individual, "minor" results that go in an ideologically inconvenient direction and, as Nima says, everyone does it to a certain extent because it is a human thing to do so.
Well, first of all, I would say that it is not only human but to a large extent, it is right, rational, and scientific. Some principles – and even "somewhat vague prophesies" – are so powerful and important that it is right to dismiss some individual results contradicting a principle as "almost certainly wrong ones" and others as "potentially misinterpreted exceptions". In my opinion, it is important not to overlook the forest for the trees. A macroscopic perspective is often necessary.
On the other hand, the macroscopic reasoning and perspective is usually imperfect, at least a little bit imperfect, and it's important to realize its limitations and the inability of a philosophy to dictate the character of valid scientific results forever. A philosophy may have "worked" for years but it may still break down on a sunny day if not a cloudy day. Philosophies aren't guaranteed to work forever; their strength boils down to collective features of established (and ultimately empirically supported) scientific findings, too.
People are trying different strategies to approach questions, different degrees of confidence in the "literal" or "microscopic" thinking on one side or the "far-reaching" or "macroscopic" or "ideological" thinking on the other side. Some of them are sometimes more successful than others so the community of researchers may constantly update the weights and decide about a sensible role assigned to the philosophical vs literal thinking about the problems.
So I believe all kinds of thinking may turn out to be superior in different contexts and I would never cherish one of them only. It's important to preserve the scientific integrity, to work hard, and to realize that any belief is potentially fallible and falsifiable. Regardless of one's focus on big-picture arguments, principles, and philosophies, a sufficient amount of results may accumulate to convince someone that his or her previous beliefs were imperfect or downright wrong. It's wrong if someone's stubbornness is infinite; but it's also wrong if someone tries to eliminate the "inertia of beliefs" because this inertia has very good reasons to exist. Nima, with his promotion of conservatism in physics, would agree even though this comment seems to be in a tension with some other assertions he has made.
The anthropic controversy is an interesting playground to think about these ideological-vs-technical issues. The anthropic-vs-non-anthropic dilemma (perhaps equivalently, anthropic-vs-naturalness dilemma) has been something that Nima has considered spectacularly important in the recent decade. It's the ultimate crossroad of science for him. It made him excited and led him to write numerous papers – sort of on both sides of this aisle. It's good that ideologies may do some creative work.
But others, like myself, would never share this excitement. I think that neither the existing non-anthropic (or "natural") solutions nor the existing anthropic ones look like a satisfactory final answer to the questions that these paradigms are supposed to answer (especially why some small parameters in Nature are so small).
The existing anthropic explanations are largely vague, illogical, ill-defined, acausal, and unpredictive, among related vices. The existing natural explanations of all the small parameters either contradict some empirical data or fail to be really natural or are heavily non-unique, among related vices. In my opinion, that's why it is wrong to pretend that we have reduced the possibilities to a shortlist of two candidates. We don't have any two good candidates. The true answer to all these "anthropic" questions may very well be e.g. a mechanism that divides each hierarchy to numerous "minor hierarchies"; or it may be a solution that lies in between the anthropic one and the non-anthropic one or a solution that renders the question "is the anthropic principle right" meaningless or ambiguous (some nearly unimaginable hybrid). We just don't know. We don't have good "final models" which is exactly the situation in which one should stay open-minded.
But when it comes to the very ability of "scientific ideologies" to stimulate some work, I think it is a good force of Nature. Science is not only a competition between individual detailed technical hypotheses; it is a competition between "big paradigms" or "ideologies", too. It's important that the battle obeys the scientific rules and that no candidates are eliminated "a priori" (the "a posteriori" elimination, i.e. falsification, is right and essential, however). At the end, the ability of technical results to support or disfavor "ideologies" is one of the main reasons of their existence – and I think that this claim is especially true in research that has no applications because "big questions" are among the primary motivations of the pure scientific research.
An extra comment about some particular ideologies – the "amplituhedon" and the "spacetime is doomed". The amplituhedron work and the results that led to it are amazing mathematical insights but I don't really see how they support the "spacetime is doomed" ideology. I have already discussed this issue in the second part of the diaperhedron post.
The spacetime is doomed but the space in which the amplituhedron lives is some "auxiliary space" of a mathematical character that has no direct "physical" interpretation. In some sense, I believe that every interpretation that may be called "physical" must make some references to the spacetime, to the relative positioning of objects or events (although the modern descriptions often make the very character and shape of the spacetime highly non-unique etc.). Nima and Jaroslav don't really have a "replacement" for the physical concept of the spacetime which is why so far, their space must be viewed as an auxiliary space whose ultimate purpose is just to be a tool in the intermediate steps required to make valid propositions about the spacetime phenomena at the end.
I may be more explicit. I think that the conceptual role of the space hosting the amplituhedron isn't too different from the status of the moduli space of Riemann surfaces in string theory. It's some auxiliary space. Integrals over this space produce scattering amplitudes (although the technical details are very different).
In the 1980s, e.g. during the First Superstring Revolution, people would view the concepts of perturbative string theory – including the moduli spaces of Riemann surfaces – as the fundamental ones while spacetime was already reduced to a secondary emergent object. However, I think that this way of thinking was really "undone" by the Second Superstring Revolution in the 1990s that returned the physics to the spacetime, sort of. Objects associated with weakly coupled strings were downgraded to some effective description that is only useful in a corner of the stringy configuration space. The physical claims that were valid universally, even at strong coupling, had to be reconnected with the spacetime once again.
In this sense, I believe that Nima's ideology is trying to undo the Second Superstring Revolution again and upgrade a particular auxiliary structure – analogous to those in a weakly coupled limit of string theory – to the Master. But I think that he doesn't have the evidence that these mathematical structures should be the new Master. So even his amplituhedron findings may have been done due to Nima's excitement about the "spacetime is doomed" paradigm, I think that the final amplituhedron findings don't really bring us any new evidence in favor of the "spacetime is doomed" reasoning.
If I am right, this is not the first time in the history when important findings were stimulated by some ideology that finally turned out to be very problematic or wrong, of course. For example, Einstein's search for a new theory of gravity was importantly stimulated by Mach's principle but the final result, the general theory of relativity, doesn't really endorse Mach's principle. Ideologies may play both destructive and constructive roles but it's important to separate the science from personal emotions and histories. Someone's excitement about an ideology isn't a proof of this ideology even if this someone finds something important in science!