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Comment by mhh__ | Hacker News Reader

Keep in mind that a string theorist would probably just flip all of this on its head by pointing at the total lack of progress from their detractors.

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> Keep in mind that a string theorist would probably just flip all of this on its head by pointing at the total lack of progress from their detractors.

This is just the Politician's Syllogism[0], though:

We must do something.

This is something.

Therefore we must do this.

[0] https://en.wikipedia.org/wiki/Politician's_syllogism

This "something" at very least works on some level — its a self-consistent theory that fits existing data, its competitors apparently cant.

Are the detractors of string theory saying we should stop doing fundamental physics entirely? I don't think so

> its a self-consistent theory that fits existing data, its competitors apparently cant.

My understanding of string theory is that there isn't even a proper string theory variant of the Standard Model, and that most of the models people are trying out are basically toy models that kinda resemble, say, QED. This means it's not even coherent enough to ask the question if it fits existing data, which is part of the premise of it being "not even wrong."

> its a self-consistent theory

Nobody knows this since there is no exact mathematical formulation of "the theory" to begin with.

> that fits existing data

Nobody knows this either since nobody has derived either General Relativity or the Standard Model of particle physics as an approximation to any string theory model.

General Relativity is a straightforward consequence of basically any form of string theory.

That's entirely true, but the problem is ST gobbled up a large share of resources and personnel in theoretical physics for decades. Smolin in particular is arguing that other ideas should get a fair shake.

Disclaimer: I’m a total outsider, not in physics or even academia, so what do I know? But threads like these make me think that some entire branches of science are less and less about the search for truth, and more and more about establishing a “personal brand” made up of a bundle of research and papers, recruiting supporters, and defending that bundle from detractors. It sounds exhausting and not what comes to mind when I think “science.”

I think you've accurately described academia in general, and (if abstracted slightly further) the human condition. It's astonishing we've made any progress at all.

Broader sociological problems aside for a second (academia does have issues for sure), one should keep in mind here that string theory is just a small subfield of physics and is not at all representative of physics as whole (or even theoretical physics). So don't let the pathologies that have developed there colour your view of physics or science generally.

"A new scientific truth does not triumph by convincing its opponents and making them see the light, but rather because its opponents eventually die and a new generation grows up that is familiar with it" - Max Planck

I'd like to push back on this sort of gently but in a few ways.

1. Scientists are entirely human. Sometimes I think people expect more from both science and scientists. In the end, getting knowledge is hard. I have a copy of the Oxford Handbook of Epistemology which I keep on my night stand and every once and awhile it amuses me to read the first few chapters the upshot of which is "Fuck, we don't know how we know anything, really." Science works by having lots of unfruitfrul research programs. I won't say that research programs don't get "pathological" from time to time, in the sense that more energy is invested in them than it should be, but this is often only really discernible in retrospect. Even if a naysayer turns out to be right after a program has been explored, it doesn't mean that the naysayer was justified before the cards were all on the table.

2. Whether we like it or not, the search for truth is a practical matter, involving courting reputation, earning research money, winning war of ideas. This isn't so much new as it is profoundly more democratic than it used to be. Newton was famous for aggressively defending his reputation, to the point of arguably claiming to have invented things that he did not. Now we just have many, many, many more humans involved in science.

The difference between good science and bad science is contingent on whether the search for funding aligns with the search for truth.

Same as it ever was, I think. It's just that when you look back in retrospect, you spend all the time talking about the paths that turned out to be successful. The history of science is littered with now-forgotten theories that, in their day, dominated their fields.

Textbooks and encyclopedias on physics that I'm familiar with do go there, though. I distinctly recall reading a lot about the fight between proponents of light-as-particles vs light-as-waves (and various experiments along the way that moved consensus), including various aether theories. Or, say, how the model of the atom evolved from simplistic solar-system-like stuff to probabilistic electron clouds etc. Even in middle school textbooks there was discussion of the originally dominant theories of gravity ("heavier things fall faster" etc) and how they were disproven. I'm not a science historian, and it may well be that various important details there were wrong, but nevertheless you did get a very clear impression that scientific progress involves a lot of loops, detours, and dead-ends.

> But threads like these make me think that some entire branches of science are less and less about the search for truth, and more and more about establishing a “personal brand” made up of a bundle of research and papers, recruiting supporters, and defending that bundle from detractors. It sounds exhausting and not what comes to mind when I think “science.”

Indeed, this is exhausting and many scientists do hate this, but in the existing system, if you don't play by these rules, you will have difficulties collecting funding and/or a tenured position.

I like Loop Quantum Gravity, if only because I really enjoy reading Carlo Rovelli's stuff and listening to his talks, but it's really not going any better than String Theory is. Smolin's not wrong in ST getting too many resources, but every indication we have is that the competitors seem to have all of the exact same issues. We have no idea how to test them, their predictions are often wrong and require bolting on revisions, etc. If anything, that grant money and brainpower should likely be redirected to totally different fields where we can actually make progress.

Particle physics is in a really weird place. I'm a layperson, but it seems to me we're in a position where either our technology is extremely far off from being able to collect the data we need, or we've missed something very fundamental in our approach, and it's going to take a major rethinking to figure anything out. I am not optimistic that we're going to make any significant headway here in my lifetime.

Though, as a layperson my opinion on all of this isn't worth the electricity used by my computer when writing it.

AFAIK part of the problem is that the experiments needed to provide evidence for these theories either require insane energies, particle accelerators the size of Earth's circumference or even larger, or convenient access to a black hole.

This seems like a fundamental problem. If data is out of reach, we're left with nothing but noodling around with mathematics and simulation.

...which means nothing, especially since string theory didn't solve physics either.

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