On June 28th, The Guardian's Ian Simple invited David Berman, a very good string theorist whom I know, and Eleanor Knox – both of them did great – to discuss the question
It's possible that people need this much time. It's possible it won't be enough. It's possible that mankind will turn into hopelessly stupid apes again. But it's also possible that the progress could be faster. Clearly, the estimates how quickly a theory of everything is going to be found depends on the recent advances and their extrapolation – on the people's enthusiasm and self-confidence which, in the case of intelligent people, reflects some actual facts or experience. That's why sensible people such as Witten found it totally possible in the mid 1980s or mid 1990s that the theory of everything would be completed within weeks.
While Eleanor and David did great, the whole podcast was framed as a modern "trial against Galileo". Throughout the show, the actual scientists were expected to defend themselves and apologize. I find this basic formatting absolutely unacceptable. It is just another manifestation of the political correctness that has run amok.
Aside from David and Eleanor, Sample (remotely) invited a well-known "vanilla critic" who clearly had nothing to say about string theory whatsoever because he knows virtually nothing and couldn't possibly get a well-deserved passing grade in the first undergraduate string theory course. That stuttering, unpleasant vanilla critic was only repeating hostile clichés "it is not science", "it is not testable" etc.
String theory unquestionably is science and it is in principle testable. What is't scientific are Inquisition trials where scientists and their theories are being attacked by brute force, without any legitimate technical arguments whatever.
The real systemic problem isn't one of the three participants who clearly contributes nothing. The real systemic problem is that Ian Sample, the host, was basically standing on that wrong side in much of his monologues. In effect, there were two plaintiffs and two defendants at this Inquisition trial. So at the very beginning, we learned from Sample that string theory was "controversial" and that no evidence in favor of string theory has been found in 35 years. What? What the hell are you talking about, Sample? 2019 minus 35 is equal 1984 – which is not only the Orwellian year but also the year when the First Superstring Revolution Started.
A majority of the evidence in favor of string theory has been found after 1984.
As David and Eleanor were trying to explain – but too politely, so that Sample couldn't get it – the evidence that assures competent physicists that string theory is here with us to stay has a more complicated, mathematical form than what unrefined minds such as Ian Sample's can comprehend. Everyone who has tried to look into this question but concluded that "no evidence in favor of string theory has been found for decades" is simply an intellectually inferior person who is incapable of becoming a theoretical physicist in 2019. The statement is demonstrably wrong – spectacularly wrong – but only smart people may understand the proof.
What is so difficult about this simple point? What is difficult is that it is politically incorrect – all the people who have no chance to understand the contemporary science because they are too stupid must be considered as "equal", anyway. Well, they are not equal. What they have to say about science is smaller than what string theorists have to say by many orders of magnitude. They're just adding noise. And if they invent an alternative to string theory, they are always pure crackpotteries. There is no real alternative to string theory.
At some moment, Sample was pushing the scientists to defend the thesis that gravitational wave detectors will be the experimental apparatuses that will test string theory. But none of them actually wanted to say that "the gravitational waves are the experimental silver bullet" for string theory by themselves. David said that it was just one among a huge number of rather far-fetched possibilities. The real point is that string theorists are working on strategies to advance knowledge that don't have the form of any simple-to-imagine experiment such as LIGO – strategies that are perfectly alright and contribute positive (and in almost no cases, negative) evidence that string theory works but strategies that intellectually limited people such as Sample simply cannot get.
They cannot get it because they misunderstand even the simplest point that the judgement what is right and what is wrong in theoretical physics usually depends on refined proofs, calculations, and arguments that heavily depend on mathematical details. They have never witnessed an example of a mathematical argument that actually mattered – and that's why many of them assume it is impossible. They are only imagining that proofs may be of the form that the average mammals could understand as well. All their conclusions are intuitive. But the average man's intuition breaks down in high energy physics near the Planck scale. Well, it actually breaks down much earlier.
The implicit assumption that string theorists are obliged to build some realistic experiments is just pure garbage. String theory has been a hardcore theorists' activity since the beginning. Also, from the beginning, it looked way more likely that the extra dimensions would be too small to be seen by doable experiments; for a while, larger extra dimensions were considered but even in that epoch, this possibility was considered far-fetched. There is nothing wrong about it. The claim that all physicists must be doing experiments is the Aryan Physics from Nazi Germany and it is complete nonsense.
However, the numerous string vacua with several compactified dimensions have been proven to be exactly as consistent as the vacua with 10 or 11 large spacetime dimensions. The claim (repeated on the show) that string theory predicts a wrong number of dimensions is simply false, much like almost all statements about the science itself that Sample and the vanilla critic made in the discussion. No, we don't live in 3+1 dimensions if you count the dimensions carefully.
Sample was also asking what the string is. Eleanor and David were attempting to tell him that string theory was just a name and instead, there's difficult mathematics he is unlikely to get. That's one important way to look – it is important because people should be explained that the arguments follow mathematics and not some intuitive opinions about the piano strings or something like that. Another way to look is that the string is a real 1-dimensional curve in space, an infinitely thin fundamental object. The positions and speeds of its points have to be treated as quantum variables etc. (and at stronger coupling, they cease to be uniquely fundamental) but it is fundamentally obtained from something like a real thin rubber band. Does Sample really need to ask that strings are really strings in 2019? String theory has been around for 51 years and for some 48 years, we've known that it was a theory that could be extracted from strings. Sample himself has discussed string theory many times. Is it really appropriate for a top U.K. newspaper to ask "what is a string"? And if a listener has no clue "what is a string", does it make sense for him to listen to much more complex questions about the status of string theory? Isn't it clear that such an incorporation of the listener is fraudulent? If someone doesn't even know "what a string is", not even in some laymen's caricatures of the answer, then he is very, very far from meaningfully thinking about the state-of-the-art questions of theoretical physics. The implicit claim that he can follow the arguments is clearly a lie.
Also, we heard from Sample that string theory was more "controversial" than any theory in the history of science. Oh, really? And what about heliocentrism? Darwin's evolution theory? Relativity in Nazi Germany? Genetics in the Soviet Union? And indeed, quantum mechanics among the West's neo-Marxists of the recent 50 years? Important scientific theories often find people who oppose them. When the theories are correct, the people opposing them are pretty much idiots. That's the case of string theory's critics, too. The more idiots and the louder idiots you can find, the stronger the "controversy" will be. A theory's being "controversial" doesn't say anything whatsoever about the intrinsic properties of the theory itself. It says more about the critics. If you focus on some people's emotions and not scientific arguments themselves, then you are not doing science, you are not looking at the Universe in the scientific way, Mr Sample.
Sample has also asked: How is it possible that the brilliant young people keep on starting to work on this theory, despite Sample's and vanilla critics' constant efforts to sling mud on string theory if not ban it? Isn't it because these young people are brilliant? While you are not? Brilliant people can figure that string theory is the state-of-the-art framework in which the most accurate theory of Nature must be studied as of 2019. They can figure out that the talk in the newspapers is just misleading or downright deceitful junk which is not addressed to them. People who aren't brilliant – and especially, people who are complete idiots – can't figure this out. They're effectively on par with the average monkeys – who are willing to absorb moronic slogans from vanilla critics. And that's why they get easily manipulated by the garbage in the Guardian and similar cesspools.
But the average true monkey can usually understand that it is a monkey – different from the humans. The likes of Sample apparently can't get it. He seems incapable of even inventing the answer – or "possible answer", from his careful viewpoint – that the reason why brilliant people do string theory and he doesn't is that brilliant people can get it and the stupid people can't. He can't invent "create" the possible explanation of the young people's interest – namely that they are right and he is wrong. The fact that the smart people still say that string theory is correct looks like some giant conspiracy theory to him. He would clearly prefer an explanation involving the extraterrestrial aliens who keep the best theoretical physicists – young and older – hostage.
Sample talks about career prospects etc. But he remains completely silent about – and it seems that he is totally failing to get or acknowledge – that "beautiful minds" are actually driven by their curiosity. They want to understand how the Universe works. It isn't about careers. A mediocre person like Sample isn't curious and isn't driven by any forces besides the animal instincts or his desire to make some money but he should be able to understand that some people simply are better and more "beautiful minds" than he is. These activists refuse to get it. Note that all the filthy anti-physics websites talk about the money all the time (how they can rob this group of physicists or another of some money) – and they don't care about the actual science. This clash is really both intellectual and ethical, string theorists are generally the good guys, and the anti-string individuals are the villains.
Eleanor and David were effectively making the same points as I do but they made the statements in such a careful and polite form that they were unavoidably overlooked – and sometimes deliberately overlooked. I think that they sounded pleasant – but too pleasant, like some folks flying in the clouds who are disconnected from the Earth. With this attitude, while facing aggressive, ignorant, prejudiced bullies and chronic liars such as the vanilla critic, science becomes indefensible in the broader society. If scientists can't comprehensibly convey the point that critics of string theory are critics of string theory because they are low-IQ and/or dishonest biological waste or jealous because they can't be better, this point will just not get to the listeners, and it will be unavoidable for science to be increasingly treated like Galileo.
David, you probably can't explain exotic branes in M-theory to too many Guardian listeners – although I do think that a healthy society would have radio stations that would try to explain exotic branes, too. But the sociological fact that various people who discuss these things belong to groups that differ by some 40 IQ points and by the equivalent of 5-10 years of intense study is something that you and others should be capable of communicating. What is at stake is the public's understanding of the very existence of science – and its basic preconditions such as the freedom of research without bullying, and hard work where some loudly pronounced demagogy isn't the ultimate weapon.
It's questionable whether it's a good idea for scientists to help the journalists with creating content whose anti-scientific goal is determined at the very beginning. I think that Sample has decided what the "story behind the discussion should be" in advance – "string theory is controversial" – and nothing could change that plan because the likes of Sample don't care about the facts and arguments as they appear. Isn't a string theorist who helps this content to be produced a useful idiot unwillingly helping the ongoing campaign to delegitimize science? Isn't it wiser to acknowledge the reality – that lots of journalists are just very hostile towards science – and ignore or boycott these journalists?