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Comment by farts_mckensy | Hacker News Reader

Theoretical physics are theoretical; that seems to be the crux of her problem. And in that light it makes sense that she's become an influencer who makes content instead of someone who devotes most of their time to advancing the science. Yes, oftentimes people will be paid to work on problems, and they'll end up in a cul-de-sac. That will be the case for the majority of the field in the case of something like quantum physics. But if we pay enough of these people to sit in rooms and work on problems, maybe one of them will figure something out. That's how science progresses.

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> enough of these people

There’s more than enough already. (And, historically, you only need less than a dozen.)

> (And, historically, you only need less than a dozen.)

This seems initially like a pretty outlandish claim to me. Could you clarify what you're referring to here?

I'm not the one you're replying to, but the claim seems very reasonable to me.

Fundamental breakthroughs in how to think about scientific subjects usually are created by fairly small groups of people. A lot more people are involved in popularizing it, and then filling out the details. But it is rare for it to start with a large number of people.

For example that list in the case of quantum mechanics was Max Planck, Albert Einstein, Niels Bohr, Louis de Broglie, Max Born, Paul Dirac, Werner Heisenberg, Wolfgang Pauli, and Erwin Schrödinger.

You can think of this as the scientific version of the 2 pizza rule.

Humans sure love this story. A dozen Founding Fathers created the United States. A dozen physicists invented quantum mechanics. A dozen innovators caused the Industrial Revolution. It's always wrong.

Ask any of those dozen people where they got their ideas and (if they're honest) they'll each have another dozen people to name, and so on. Ask them who made minor contributions and suggestions and they'll again have dozens of people to name. Science is an ever-expanding body of work that always builds on its past successes and it's the height of naivete to reduce humanity's effort in a subject down to its few most visible people. It makes for good stories and trivia questions, but it's extremely far from the actual truth.

And even if it were true: how could you possibly identify those dozen people beforehand? It'd be like walking into a publishing house and proclaiming that everyone there is stupid because they waste all this money on books that don't end up best-sellers. Why don't they just only invest in the future best-sellers? Are they stupid?

I partly agree. A conceptual breakthrough always rests on a foundation to which many contributed. All of whom, in some sense, contributed. But my reading of history says that the reconceptualization that leads to intellectual breakthroughs themselves usually only involve small numbers of people.

If you've read The Structure of Scientific Revolutions, what I'm saying is that new paradigms are usually created by very small numbers of people. But they have both a foundation and their further success from the contributions of many.

I'm very much not offering an opinion on a great man theory of history in fields outside of science. Your example of the American Revolution is entirely off topic.

I'm also very much not saying that who will contribute what is in any way predictable. At best, the necessary collision of circumstances to make the breakthrough possible is chaotic, and therefore cannot be predicted. Nor did anyone else. The original point a few posts up was that, even if though there might be a haystack of clearly wasted effort, there may still be a needle powerful enough to make up for the rest.

All good points, but remember the claim in question was:

> But if we pay enough of these people to sit in rooms and work on problems, maybe one of them will figure something out.

and the response that you called "very reasonable" was:

> There’s more than enough already. (And, historically, you only need less than a dozen.)

So you were agreeing with someone who said we are paying too many physicists. There are too many people studying this problem. Okay, let's get rid of some then. Which ones?

> I'm also very much not saying that who will contribute what is in any way predictable

Uh oh, then how do we know who to get rid of? Which physicists should we not be paying? The claim that we should fire a bunch of scientists because we "only need less than a dozen" is nonsense, and you called this claim "very reasonable", with more examples. But maybe I should have replied to that person instead. It's a little awkward trying to have an N-way conversation when you can only reply to one response at a time.

The statement that there's more than enough, is not the statement that we should be firing them. It's a statement that we don't want more.

But if we had to fire some, I'd recommend ones who are not willing to do research outside of oversubscribed ideas. That's because the lack of success of existing lines of research means that additional effort there is less likely to work out than looking at less overpopulated approaches.

>> For example that list in the case of quantum mechanics was Max Planck, Albert Einstein, Niels Bohr, Louis de Broglie, Max Born, Paul Dirac, Werner Heisenberg, Wolfgang Pauli, and Erwin Schrödinger.

Those were not the only people working in that field at the time. Not by a long shot. In order to have pioneers in a field, there has to BE a field with a bunch of people in it.

You're right that these were not the only people working on the set of problems that lead to QM. Lots of people were thinking about the same problems at the same period of time. And lots more added to it later.

But what key concept underlying how we now think about QM doesn't go back to this list of people? OK, add Richard Feynman if you want to include the second breakthrough to QED.

Ideas that look like conceptual breakthroughs can usually be traced back to small numbers of people. Ideas that look like progress usually trace back to much larger groups.

> What key concept underlying how we now think about QM doesn’t go back to this list of people?

Off the top of my head: quarks, and therefore the existence of the colour charge quantum number; and the Higgs field.

All of the people in the list were also building on prior research by the likes of James Clerk Maxwell and Ludwig Boltzmann. Einstein himself said “I stand on the shoulders of Maxwell.”

There are other obvious candidates for inclusion like Henri Poincaré, Hendrik Lorentz, Satyendra Nath Bose…

You are adding people by changing the discussion to one where the point no longer makes sense.

I'm focused on how many people were needed to make the conceptual breakthrough from classical thinking to quantum thinking. I'm very explicitly not considering how many people were needed to further develop the idea of QM from there. I'm also not considering various other conceptual breakthroughs. Just how did we go from, "here's a bunch of weird observations that don't make sense," to, "here's a way of thinking that lets us explain them."

The discovery of quarks, color charge quantum number, and Higgs field are part of the further research, and so aren't relevant.

Maxwell was firmly part of classical mechanics. He provided a key foundation, but was not part of the transition.

Boltzmann was key to the creation of statistical mechanics. While converting classical statistical mechanics to QM was a key part of the success of QM, this was not work that Boltzmann was engaged with.

Henri Poincaré did indeed spend a fruitful few months on QM in the last year of his life. Sure, add him to the list.

Hendrik Lorentz contributed to SR, not QM. Yes, he did lecture on SR in the 1920s, but he was lecturing on what Schrödinger has already discovered. He did not originate new ways of thinking to QM.

You have an extremely good point about Satyendra Nath Bose.

So most of the topics you added were not part of the key shift that I was talking about. Most of the researchers that you added did not directly contribute to that theoretical transition.

We need lots of people to create the foundation. Lots to build out the new framework. But very few are needed to develop the new way of thinking that scientists transition to.

[flagged]

"Please don't post shallow dismissals, especially of other people's work. A good critical comment teaches us something."

"Please respond to the strongest plausible interpretation of what someone says, not a weaker one that's easier to criticize. Assume good faith."

https://news.ycombinator.com/newsguidelines.html

Hardly a shallow dismissal dang, as the replies show. It’s a very valid critique of where it has ended up, and goes right to the heart of the underlying problem.

The challenge is if it’s intentional from the start, or merely ended up being intentional at the end eh?

And the folks arguing that the underlying critique are false, as shown in the follow-ups, are wrong.

If anything, it’s just getting downvotes because people don’t realize how on the nose it actually is, near as I can tell.

Sorry, but your GP comment consisted of nothing but putdowns—not just of an entire field but of the people working in it. That is a classic shallow dismissal in the sense that we use the term. Not a borderline call!

I guess we have a different definition of put downs eh? Noted, thanks.

I think that you have half a point. You're absolutely right that just because people are paid to think about things, doesn't mean that they are making progress. And there is a lot of evidence that this is true today in the foundations of physics.

However string theory was not intentionally untestable. In https://www.youtube.com/watch?v=eRzQDyw5C3M she gives a good history of why it was originally invented, what testable predictions it made, how it failed those tests. And then how string theorists who were trying to find relevance for their work tried to keep it going as it stumbled into being untestable.

Fair point, I guess. It’s easy to also see how it just mostly ended up there. Still. A problem.

This is a very cruel reading of string theory. Intentional? What?

Exactly. Consistently untestable and unfalsifiable claims for decades has to be seriously questioned at some point, and I think we're well beyond that point. This is especially true for string theory. I'm particularly fond of how Angela Collier laid out the timeline of string theory in her video on it[0] as well as the consequences that science communication is now facing as a result.

[0] = https://www.youtube.com/watch?v=kya_LXa_y1E

The same could've been said of atomic theory, neutrinos, gravitational waves, the higgs boson, cmb radiation, plate tectonics, and quantum mechanics at various points in time.

That statement is only true for a few of the things on your list..

Yes, it took a couple of decades to test the existence of neutrinos. But, for example, general relativity was successfully tested within 5 years of being published. Gravitational waves were a prediction that took decades before we could test them, but the theory itself had lots of other verifications.

To date string theory has had many predictions that leads to failed tests. But not a single successful test in its favor.

Weren't those all arrived at from a series of falsifiable predictions? What does string theory even predict that can be tested?

As a non string theorist my understanding was that string theory actually makes quite a lot of empirically verifiable statements, just that those statements are only interesting at either never or extremely high energies.

I think ppl are asuming that sting theory comes from the meme about turning 1+1 = 2 into some massive integro differential equation. The world is rarely so simple.

I’ve heard that it also predicts at very low precision, some values that are practically measurable, and, unsurprisingly for how little precision these predictions have, these predictions are correct (I.e. the experimental results are within the predicted range).

(Or, maybe “a prediction” rather than “predictions”? I only heard about one, and I forget what it was.)

I think the prediction you may be referring to is supersymmetry, which was apparently empirically disproved by the LHC, or at least the supersymmetric extension to the standard model was disproved.

https://www.sciencenews.org/article/supersymmetrys-absence-l...

I am aware of no case where it clearly made an advance prediction of any behavior that later turned out to be true.

I'm aware of quite a few where they managed to "predict" something we already knew.

That said, they've made so many "predictions" that I'm sure that some likely worked out by sheer coincidence.

Oh, yes, I meant predict a value we had already measured at the time the "prediction" was made. I should have made that clear in my original comment. I would add it now except that the editing time has run out. Maybe I should have said "postdicted".

Actually, I think the value might have been something like, the electron mass? Or something like that. (Which, obviously, had been measured before string theory made a "prediction" of it.)

You are making it sound as though string theorists are asserting some kind of flying spaghetti monster theory. Do you think these people are not genuinely interested in advancing science? That's an ad hom fallacy. There is a difference between a hypothesis being conceptually unfalsifiable and a hypothesis that is incredibly difficult to test from a practical standpoint, or impossible with present energy constraints.

I don’t think the mistake made is exactly an ad hom fallacy? I agree with the rest of your comment though.

No, not really. All of those had reasonable, technically addressable methods for testing.

No you couldn’t. And it’s been 80 years now!!

All of those things you name came directly out of attempts to create testable hypotheses from experimental observations, and all of them were tested as soon as anyone could build an experiment apparatus or gather the data to do it. Which didn’t take that long considering the extreme engineering difficulties in actually building the apparatus for some of them.

String theory has avoided testability it’s entire existence, nearly a century now, and no one that I’ve seen is even attempting to make an experiment to try to test it - because at this point it’s clear that no one on the theory side is interested in making a testable hypothesis. That isn’t luck, that’s talent and hard work.

It’s one of the most absurd grifts I’ve personally seen play out so far.

80 years? I would date its birth as 1968-9 (Veneziano), it’s hard for me to imagine calling prior work than that as “string theory”. But never mind that—the bigger problem with this (quite common) argument is that everything about quantum gravity, not just string theory, has avoided testability because our other theories are too good, and because we’re limited to doing experiments on Earth with equipment built on human scales with human budgets, and that’s just not where quantum gravity would naturally make itself known. So really this argument just suggests we shouldn’t study quantum gravity at all. Maybe that’s your actual opinion—it’s a waste of time if we can’t access the Planck scale, we should table it all and sit on our hands until we can. But string theory really is quite interesting to study, stuff like AdS/CFT is just really surprising and magical when you get what it’s about, and it would be a real pity to not pay the meager salaries of theoretical physics just because of pessimism. String theory is so far from fully understood! It’s actually…really hard!

BtW I think you got this 80 years number from looking at the earliest date on the Wikipedia page. You might want to read it more carefully. Not everything leading up to string theory is string theory.

Fair enough - 50 to almost 60, not counting s-field precursor work.

I’m not saying string theory isn’t potentially interesting from a mathematics perspective, I’m just saying treating it like physics (which is, explicitly about testable/falsifiable theories) is BS.

If we were honest about it, it would be a maths speciality eh?

At least until there are more clear attempts at making testable hypotheses.

But that would cause other issues with funding I imagine.

If quantum loop gravity comes up with a testable hypotheses, then hey, maybe I’m wrong. But so far, not so much yeah? And I’m not talking ‘we’d need to spend a lot of money to test it’, I mean an actual testable/falsifiable hypotheses at all.

There is no evidence to suggest that string theorists designed the theory to be untestable.

That proves it!

I mean, you should prove they didnt. If that sounds unreasonable we've made progress. Prove we didn't?

Ill let myself out

After this much time and that much work, how is it possible for a physics theory to not have a single testable/falsifiable prediction without it being intentional? It has been over 80 years. [https://en.m.wikipedia.org/wiki/History_of_string_theory].

The evidence is in the absence.

It predicted supersymmetry, which has been experimentally disproved.

The kind of supersymmetry you’re referring to (global spacetime supersymmetry) is not required by string theory; this is a common misconception. Looking for super partners in a collider is actually only telling you about global supersymmetry, which unlike local supersymmetry is not a universal feature of string theory at low energy, in fact the opposite, it is probably non-generic. It so happens that a class of appealingly simple vacua do have this property, which led to some inappropriate optimism among string theorists that has entirely abated with more experiments. Unfortunately this has been widely misunderstood to rule out the whole enterprise of string theory, which is unreasonable for the reason stated above, it is much more likely to not see SUSY below the Planck scale. [0] (Unless you just like to mock string theorists for hoping that the universe would be kind to them.)

Also global supersymmetry has not been experimentally disproved (how would you do this, even?) but it is true that current or even near-term experiments are not nearly sensitive enough to get close enough to answering this definitively, which is obviously upsetting.

[0] https://ncatlab.org/nlab/show/string+theory+FAQ#DoesSTPredic...

Not intending to mock anyone and I don't know nearly enough physics to have a credible opinion either way. Thanks for your explanation.

Don’t worry, I didn’t think you were :) you’re welcome!

How is it "intentionally untestable"? I get that it is practically untestable, but as far as I know, there are people working to try to find some possible tests.

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