- Hold fire! This epic vessel has only just set sail...
He starts by saying that the caustic attacks on string theory are perhaps the strangest kind of controversy that reverbates through the blogosphere. If you think about it, it is really weird that such an abstract thing that used to be interesting only for a few geeky physicists becomes a target of vitriolic public attacks in books, blogs, and newspaper articles.
In the blogosphere, everyone is an expert and everybody can offer his or her opinion. All opinions are equal, Susskind jokingly writes, resonating with some bloggers and commenters who are however dead serious about it. The criticism has turned into a drumbeat. Journalists with high-school physics education suddenly condemn the subject in places as unprobable as the Wall Street Journal, the Financial Times, and the New York Times Book Review. ;-)
What in the multiverse is going on, Susskind asks? Have all the physicists at all the top U.S. schools really lost their minds? Do they follow secret priests in order to abandon good scientific manners? Or is it more likely that the critics are grumpy conspiracy theorists who are upset because they are ignored? People who want to gain 15 minutes of scientific fame without the real work?
Susskind, who also appeared in the media with his Strange But True description of the Planck temperature on Thursday, compares the current situation in physics to the late 15th century in which the Atlantic sea of ignorance - analogous to those 15 orders of magnitude of ignorance at the energy scale - became irresistable for curious adventurers. Most people considered them crazy, especially the frightened fuddy-duddies and derisive kibitzers from the Chicken Little Society who proclaimed the folly of sailing more than 80 kilometers from shore - in fact, not even folly. ;-)
Crossing the Atlantic? What a waste of sailors, ships, time, and money.
But courage is not enough. One needs to learn how to construct a seaworthy vessel. If you don't construct a reliable ship, you will face, well, troubles with your vessel. ;-) Susskind offers many details about the wrongly designed ships and the celebrations of their captains as the ships keep on sinking.
Susskind then colorfully describes who the main kibitzers (Peter Woit) and troubled shipbuilders (Lee Smolin) are and ends up identifying Gerard 't Hooft as a thoughtful critic who cares about things like a real diversity of ideas and who would never use bogus pseudoarguments such as "untestability" or "it takes too long". Needless to say, the main center of string theory, a college in New Jersey, doesn't get an "A" from diversity of ideas. Princeton is also criticized for suggesting in the mid 1980s that the theory of everything would be a matter of months or years. They were wrong but unlike Susskind, I don't think that their reasoning was unreasonable.
And where is the ultimate victory? Hold fire. We're not there yet. When we arrive, it is likely that the final theory will resemble the current form of string theory as much as the modern ships resemble the 15th century vessels.
Philip Anderson, a condensed matter physicist and a 1977 Nobel prize winner, has a significantly less thoughtful essay about a similar topic in THES, too (subscription required). It is full of various comparisons with religion, the kind of ideas that we really can't find valuable because they're not valuable. Anderson also humiliates "my" quote "...is the language in which God wrote the world". I guess that he would be more cautious had he known that this is a quote by Galileo, a co-father of modern science, about mathematics: it's a nearly 5-star quote, by the way.
Imagine that we would accept this level of discussion. What would we be saying all the time? Probably something along these lines: Condensed matter physics - and superconductivity in particular - has made the last theoretical progress around 1972. Since that time, superconductivity was a form of medieval alchemy, attempting to mix atoms in random ways, assuming that it is important to develop a universal cure for everything called the hi-T_c superconductor, with no useful results. The last incremental minor result was a 35 Kelvin superconductor in 1986, twenty years ago. Since that time, the society has been wasting much more on the useless medieval superconductor alchemy than it is investing into string theory. And the results were exactly equal to zero. Blah blah blah.
Do you know why you never read this sort of comments from your humble correspondent? It's because I realize that condensed matter physics is an important and legitimate field of science and the (almost) best people that the field can get are doing their (almost) best they can in order to find interesting problems that are close to their knowledge and in order to make progress. And it's also because I realize that with my limited experience in their field, my general comments about condensed matter physics are likely to be dumb. I don't know why Prof. Anderson can't understand that the same is true in the context of his opinions about high-energy theoretical physics. I don't know why he doesn't realize that if he tries to say some wisdom about internal symmetries of the Standard Model, string theory, and their mutual relationships, they are very likely to be dumb.
Anderson also argues that physics is getting "perilously close" to validating postmodern theories about science being a social construct. More precisely, Anderson is getting "perilously close" to the postmodern way of thinking. Even if you imagined that string theory is nothing else than nice mathematics, do you think that mathematics itself validates postmodern thoughts about exact sciences being social constructs? I don't think so. Any field of science, if it is done by good thinkers, is looking for the best concepts, constructions, and ideas, and eliminates those that don't work. That's true in condensed matter physics, high-energy physics, as well as mathematics. There is no universal prescription for the relative importance of the experiments that we could assign to all these fields and this fact can't confirm postmodern theories.
Things that are social constructs are dictated by the opinions of humans and their feelings and interests. In mathematics and theoretical physics, the value and validity of ideas is determined by strict logical rules from their agreement with the existing body of knowledge which goes well beyond the facts that can be directly seen in experiments.
Do you really think, Prof. Anderson, that the hypothetical criticism of condensed matter physics above is how broader questions about science should be debated? One should be ready that if he doesn't tell the specialists in a field something about physics - e.g. what happens when you collide particles with nearly Planckian energies - they can't take him too seriously as a voice in high-energy physics just like we don't take seriously various authors of anti-science books.