Prof. Sabine Hossenfelder has a great article on the lack of progress in fundamentals of physics: "The present phase of stagnation in the foundations of physics is not normal " [1]
Choice quotes:
>We know this both because dark matter is merely a placeholder for something we don’t understand, and because the mathematical formulation of particle physics is incompatible with the math we use for gravity. Physicists knew about these two problems already in 1930s. And until the 1970s, they made great progress. But since then, theory development in the foundations of physics has stalled. If experiments find anything new now, that will be despite, not because of, some ten-thousands of wrong predictions.
>Ten-thousands of wrong predictions sounds dramatic, but it’s actually an underestimate. I am merely summing up predictions that have been made for physics beyond the standard model which the Large Hadron Collider (LHC) was supposed to find: All the extra dimensions in their multiple shapes and configurations, all the pretty symmetry groups, all the new particles with the fancy names. You can estimate the total number of such predictions by counting the papers, or, alternatively, the people working in the fields and their average productivity.
According to her, and many other physicists, there hasn't been any major progress in phenomenology since 1970s when Higgs boson was postulated.
The theories that we were dealing with around the dawn of QM/GR were relatively tractable; we could make long-enough-term predictions about the behavior of many systems and we had a library of observations that clearly and reproducibly deviated from those predictions. We had even begun to draw vague correlations among the diverging data.
Today, we have experimental data that diverges from predictions... regarding... the number of neutrino collisions we can observe in certain giant tanks of highly pure liquids, and... the scale of variation in the cosmic microwave background and long-range mass density is too small, oh, and... galaxies rotate kinda weird... free neutron lifetime measurements disagree by about 1.1%.... there's not quite enough lithium in the Universe (no, really)... good luck tying all this together into a theory of everything!
Could Einstein, being a patent clerk, have gotten his papers published these days? Is there room for non-professionals, or people outside the system to come in and disrupt it? It seems that there's a lot of disregard of wild alternative theories like quantum mechanics would have seemed in the early 20th century.
Einstein was a patent clerk at a time when government funding for science was vastly lower than today and there were research and teaching jobs for only a small fraction of physics PhDs. Also there were much fewer PhDs back then, so with a a PhD from one of the most prestigious schools, that patent clerk was in fact a physics insider.
> Also there were much fewer PhDs back then, so with a a PhD from one of the most prestigious schools, that patent clerk was in fact a physics insider.
Didn't he get his PhD awarded only after he was recognised for his work?
His “miracle year” of 1905 was, in order, on the topics of the photoelectric affect published in June, Brownian motion (his PhD thesis) published in July, special relativity published in September, and matter-energy equivalence published in November.
I think so. For Einstein, job #1 was to bring his work to the attention of some of his peers, and it's even easier to do that today, when you can just cold-email a Nobel laureate or a Fields medalist.
All name physicists are flooded with crank emails of the >>EinSteIn WaZ tEh RoNg I aM cLeVeReReR!!1!<< type.
So the odds of a truly revolutionary theory getting taken seriously based on a cold-email are significantly less than zero.
The problem is very obvious - science was both more open and more selective a century ago. There were far fewer PhDs, but they were of far higher quality. And the networks were smaller, friendlier (mostly), and more personal.
Now we have an industrialised corporate physics industry turning out thousands of PhDs a year. Most have been steered away from fundamental questions towards tweaks of the Standard Model - because anything else is career suicide and impossible to get funding for.
And after all of that, there's far more money in finance. So that's where the best people go to waste their talent.
So email a non-name physics professor. They'll probably be clever enough to recognize the revolutionaryness (?) of a theory even if they couldn't invent the theory themselves.
Math, unfortunately, has never been my game. How often does a likelihood or probability become significantly less than 0. Isn't 0 the floor? Or is 0 the 50/50 value?
I agree on the wasting of money for the wallpaper pattern that is called a degree.
My understanding is that there is still disagreement around this. One of the lines of debate is whether his wife Mileva Marić did most of the grunt-work that was necessary to prepare his papers to the level of acceptance for scientific publications at that time.
The overall narrative that seems to emerge is that he was undisciplined as an undergrad at the ETH in Zurich, and never would have landed a graduate posting, and the patent office job was a fallback. Mileva was more diligent and helped him out quite a bit.
Off the top of my head, they've made progress in quark-gluon plasma, discovering the AdS/CFT correspondence, and practical techniques for quantum computing. There's been enormous progress in computational methods, too. There's also been something very interesting going on with twistors. Oh, and 50 years ago quantum field theory was not on a formally sound footing, but now it is (not completely but it's closer). There's also a lot of progress in renormalization (RG group flow).
Oh, and don't forget about fifty years of Moore's law. We have solid state to thank for that.
I'm sure I could think of more if I gave it more time. The truth is that there have been no earthshattierng paradigm shifts in the last fifty years, but that's OK because they tend to happen once every couple centuries.
Fractional quantum hall effect is a massive one. All the action is in condensed matter. Somehow less newsworthy despite being closer to practical applications than high energy physics.
The last time we moved fundamental physics forward we got nuclear weapons. Thus, one could argue that there's good and bad parts to our current technological stagnation. Imagine having a spaceship that could travel at relativistic speeds. Can you imagine getting into a traffic accident with that thing?
I hate when people call it a “crisis” . Science has brought us amazing insights and capabilities. It's not in a crisis. They will simply have to shift gears and work on other projects if they have dug as far as they can for now with today's technology and mathematics. There is still plenty to spend human brain power on and physicists have plenty of new places to go to.
I get the same reaction. Makes me think if it isn't the current zeitgeist mindset of continuous and constant growth seeping into scientific evaluation by laypeople.
Science doesn't need to constantly grow into all directions it has achieved at the same time, it's not a market competition. I feel that sometimes it gets evaluated as such by some media vehicles...
Well, it is a crisis to people who bet their career in this field. These people are here to stay (in the field) and since there are no experimental progress that shed lights on fundamental physics, the effort of all these people are stuck in coming up with theories in existing paradigm that is still compatible with the increasingly more stringent limit from experimental physics.
They didn't shift gears and work on other projects. The whole field bet in String Theory and are stuck. Like explained in the book "The Trouble with Physics", it is a career suicide for people not wanting to deal with String Theory and still be a theoretical physicists in high energy physics.
One may say a similar crisis has happened by the end of 19-th century. All but a few peculiarity in Physics were explained by the then modern physics. Some thought theory of physics were almost "complete", and only later to find out a major paradigm shift (actually 2, quantum theory and relativity) completely changed the way we viewed physics, and now becomes our cornerstone to understand physics.
AFAIK, physicists generally like this kind of crisis, some make a career chasing crisis, because this might be the hint of new physics and the next paradigm shift.
> “Some people call it a crisis. That has a pessimistic vibe associated to it and I don’t feel that way about it,” said Garcia Garcia. “It’s a time where I feel like we are on to something profound.”
They are using past experience of a crisis (say from late 19-century) to infer what comes next is a major paradigm shift. This might very well be true, but we didn't know that. We should be optimistic about our career and the future of physics, true. But we should not be in denial that this is a crisis. There's absolutely no information (but hints) we have right now that tells you a breakthrough is coming. The next paradigm shift may happen in arbitrary far future, or may not happened at all if it is out of the reach of humanity.
Also, people don't call it crisis just because we hit a wall. But we're hitting a half century wall now (since 1970s.)
I have been as derisive as anybody about string theory's entire lack of experimentally realizable predictions. But some things give me pause. The first is its interpretation of black holes as existing entirely at the event horizon surface, with no actual space-time inside; and the black hole entropy exactly matching the set of states of strings living in the 2D horizon layer. Eliminating that singularity is a big delivery.
This seems like another case where it can deliver something useful.
I don't see your train of thought here, you first mention the lack of
"experimentally realizable predictions", i.e. not falsifiable, and then gives one of the many examples that string theory solved without being able to experimentally verified.
Why would that give you a pause? How this single example is different from all other "predictions" from string theory?
Per current understanding, “M-theory” is one of five consistent descriptions of string theory , all of which are supposed to be related by dualities i.e. each description makes certain aspects easily manifest, but they’re all equally “correct”.
Hmm. Isn't it something akin to the Fourier transform? As in: you could enjoy your square wave for its own beauty, but knowing that it can be decomposed into an infinite sum of sine waves is a pretty useful thing.
Yeah, as I say, it's easy to be derisive about string theory and string theorists. (Lubos makes it especially easy.) And, physics departments find string theorists to be the cheapest kind of hire, because they aren't always trying to get expensive equipment together for experiments.
But everybody who goes into string theory had to learn all of "real" physics first, and excel at it well enough to get into a PhD program. A lot of them must have a hankering to do real physics, like their heroes who inspired them into the field, and must be frustrated at not finding any way to do it from where they are.
Being clever people, if they can use the maths they have to suggest directions for things to try, they might make themselves useful. If the things they suggest turn out to guide reasoning toward something that will be tested, that is worth something even if the formalism the suggestions came from isn't correct in detail.
> And, physics departments find string theorists to be the cheapest kind of hire, because they aren't always trying to get expensive equipment together for experiments.
You know the joke - a university was having budget problems, so they fired the physicists and replaced them with mathematicians, who only need paper, pencil, and a wastebin. Then they had more budget problems, so they fired the mathematicians and replaced them with philosophers, who don't need the wastebin.
Eh, that's a highly uncharitable statement. Frameworks like "differential equations" or "group theory" or "quantum mechanics" also don't make falsifiable predictions (till you build a system-specific model which you can then compare against experiment) -- but that doesn't make them any less useful.
String theory in this unusual place between a physics model and a mathematical framework (that's what makes it so "fundamental"), and we are still in the process of figuring out how to construct predictive physical models using this framework. But OTOH it's been enormously useful in helping us theoretically probe and understand structural properties of quantum field theories, the implications of special symmetries, the geometry of manifolds, etc.
QM started as theory to explain otherwise unexplainable phenomenon, but explicitly provided things that could be falsified (aka tested), was immediately tested, and did indeed usefully describe otherwise unexplainable phenomenon before they were ever put forth seriously in any consistent way.
Algebra, group theory, etc. as pure math have proofs, but are definitely not (and never held out as) a physics theory.
Conflating the two is not appropriate. And saying string theory is a useful physics model while there is no way to test if anything unique it posits are true or not, may be useful mathematically - but means it’s not a physics model. Period.
That people spend so much time wedging everything into it to try to make it a useful model when it is unfalsifiable (and no one seems to have any idea how it would even BE falsifiable) is exactly the type of crisis the article is discussing.
Lots of careers built in a direction they can’t be proven wrong.
What the comment you are replying to said was that it is a mathematical formalism and not a physical model, and that they are still working to construct a physical model. So, it is not a physical theory, but the only people trained in it were first trained as physicists, and are employed by physics departments, and everything in it is constrained to fit in a physical theory.
The situation is far from ideal; there is no other plausible candidate for a physical theory compatible with gravitation and quantum field theory. But at the same time, we have literally no means to measure any case where they interact meaningfully. We can measure a fountain of cold neutrons falling in a gravitational field, but only the extremely weak field we are in. So, while it is a problem that nobody can devise a test for a physical string theory, nobody can devise a test for any other theory that would seek to fill the role.
The muon was the first WhatTheF particle discovered from cosmic rays. It and its associated quarks and leptons do not appear to participate in any physics necessary for the observable universe functioning.
And the muon vexes us again with an observed g2 moment the differs from its theoretical value greater than measurement error. This again suggests there is more unknown physics out there.
The idea that all particles should "participate in physics necessary for the observable universe functioning" is not a rational position, unless you assume a premise such as "the universe was created for a purpose."
Without such a premise, it is completely expected that not every aspect of the universe should have something to do with its functioning.
Even in pure mathematics, with no dependence on the physical universe, you have
Gödelian unprovable propositions which, as Gregory Chaitin put it, are "true for no reason, they're true by accident." If the universe did not include a physical equivalent to this, it would be quite a surprise which would tell us that something very unusual was up.
I kind of see what you're getting at, but don't think you've described it well.
My attempt to restate your position: Suppose you write a program that just so happens to log information every leap day. No one uses the information, it doesn't effect the rest of the observable output. If you delete this logging from the program, no one else notices.
The complete observable properties of the universe (the program) include this logging, but the functioning of it is not really dependent on the logging. Thus, we probably should expect that there are some aspects of the universe that are independent, they don't really matter (or at least don't substantially matter) beyond their own observation.
The logging analogy doesn't capture what I was referring to.
Logging is a feature that someone deliberately adds to an application. It has a purpose even if no-one uses it.
I'm talking about features that (a) were not intentionally designed and (b) have no "purpose" - i.e. do not "participate in physics necessary for the observable universe functioning," per the original commenter.
The point is that for a feature to have a purpose implies an intentional design. If you assume the universe was intentionally designed, then yes, one might expect all features of the universe to have a purpose. Although as Gödel pointed out, this may not be possible - even intentionally constructed systems end up with features that weren't part of the intention, but rather are unavoidable consequences of the design.
If you don't assume intentional design, then there's no reason to expect that all features of the universe have a purpose.
The point is that in empirical science, we take our observations of the universe as the starting point. And not any ideas or theories of how we think the universe should function. There was a time before empirical science took off, that the latter was still the modus operandi, a lot of beautiful theories were made but in the end science got hopelessly stuck.
It's funny that we're a bit in a similar situation now. Again we have a bunch of theories, e.g. in cosmology and quantum theory, that are based on not much more than an idea of how things should be. The Great Unification Theory springs to mind for instance. And again we seem to be stuck.
I sometimes wonder if the laws governing the universe are a bit like a Taylor series. An infinite set of terms each with a smaller effect on reality quickly approaching zero.
Are you thinking of Einstein's comment about god not playing dice? Because that's perfectly consistent with what I was saying: he was implicitly assuming a kind of "designed" universe, in which case of course we have a stronger reason to expect that all features of the universe have some purpose.
(Although this is still subject to Gödel's caveat, that even intentionally constructed systems end up with features that weren't part of the intention, but rather are unavoidable consequences of the design.)
But if you don't make that religious assumption, then the expectation that all features should have a purpose becomes unsupportable. There's simply no reason to expect that, and even the notion of features having a "purpose" is misleading metaphorical language at best.
Back to the subject of what Einstein would say, we should also keep in mind what he wrote in a private letter in 1954:
> “The word God is for me nothing but the expression of and product of human weaknesses, the Bible a collection of venerable but still rather primitive legends. No interpretation, no matter how subtle, can (for me) change anything about this.”
I'm not aware of Einstein having written anything attempting to reconcile this with his previously expressed pantheistic views and the related views implied by the "play dice" comment. That would be tough to reconcile.
Another relevant issue here is that Einstein's dice comment was objecting to non-determinism in quantum physics. But in the nearly 70 years since his death, everything that has been discovered still points to inherent non-determinism. There are some theories/interpretations that would eliminate this, like superdeterminism and De Broglie–Bohm theory. But even if such a theory satisfies Einstein's concern, it doesn't affect what I wrote - such theories don't address the justification for features of the universe, they simply model what we observe.
tl;dr: what I originally wrote is essentially a tautology that neither you nor Einstein can refute.
I strongly suspect that new high energy physics advances will come from investigating astronomically generated phenomenon.
- Gravitational Waves for probing extremely large and small objects
- Cosmic Rays for probing high energy particles.
- Solar probes to detect particles made from stellar phenomena
Oh yes, definitely new physics will come out of studying grainy footage of unidentified objects that are most likely drones or birds and well known optical phenomena that "military experts" can't seem to grasp (parallax).
Although to get anything useful out of them would require the radar data, not just the optical data. Much more certain positioning than optical cameras on fast moving platforms.
Just recently finished the Three Body trilogy and there are some interesting connections to the described dilemma in there (alien objects hindering scientific progress of mankind by messing with particle colliders, n dimensional space and weapons that destroy whole dimensionalities)
There is a slight mistake in the article. The standard model does not describe the neutrinos. In the standard model neutrinos are massless particles, but in reality they are not.
> The standard model does not describe the neutrinos. In the standard model neutrinos are massless particles, but in reality they are not.
That's a bit strong. The SM still makes good predictions for many processes involving neutrinos. We just know, since the discovery of neutrino masses, that the SM, or at least the original version of it (there are proposed mechanisms that can handle neutrino masses without modifying anything else in the SM, although they still have some issues), can only be an approximation regarding neutrinos. But the SM is pretty much considered an approximation (or, as it is usually termed, an effective field theory) anyway.
I understand your point, but depending on who you ask, the (massive) neutrinos are well described in the Standard Model framework, just we we don't know exactly what that term looks like.
So depending on who you ask, they may not regard (massive) neutrinos as "beyond standard model".
I wish they didn't use the term "crisis" for this. It's nothing like the problems other disciplines are having with respect to replication failure - where maybe the term is appropriate.
Physics can still explain / predict a shit-load of phenomena. It's not a crisis - just more work to do.
They refer to a crisis in a sense Thomas Kuhn used. The point where paradigm shift is needed. Physics has experience with it. General relativity theory was a paradigm shift following a crisis.
Kuhn is a red herring. The issue is that physicists are too far removed from experimental checks. The scientific method requires experiment to confirm a hypothesis. The separation of theory from experiment has enabled a generation (or three) of physicists to ignore experiment entirely, spending happy careers playing with the implications of unfalsifiable theories like M-Brain theory or string theory. One gets the impression of a group of very smart people hiding behind their credentials, first unwilling to let their theories be tested, and next brazenly claiming that their theories cannot be tested, and that's okay. That's not okay, and they should lose their jobs.
If that is your impression, then I suggest you test your hypothesis. Go talk to these physicists and explain your concerns. Many are approachable and responsive.
There's a book called "The trouble with Physics" written by Lee Smolin in 2006, who is a theoretical physicist himself and wrote a survey on string theory back then, involved in the string theory community and documented his observations in that book.
In short the book conclude many of them are experiencing "group-think" and over-emphasize the importance of string theory given what they can't prove theoretically as well as experimentally.
> Many are approachable and responsive.
You must be talking about some other people here. In my experience we're not. We really don't have time to address to some random people from the public on why we disagree with what they believe.
I'm not completely disagreeing with everything you said, but
> they should lose their jobs.
is too much.
You should also study the history of string theory and how their early days are miserable (too difficult to have a career as people denies string theory as physics.)
The correct approach would be to invest in string theory but also any other proponents of "theory of everything". The main issue today is that virtually only string theorist can make a career of being theoretical particle physicists.
The very fact is that there's no any other theories beyond the standard model that are falsifiable. If you require any theory to be falsifiable then no theoretical physicists can have a job. Not even the invention of general relativity would qualifies (remember although we can now falsify GM, it wasn't initially.)
I'm not a physicist nor a person who understands physics at all, but if what you say is true, wouldn't the most likely explanation be that physicists do that specifically for fear of losing their job?
I don't think physicists have better or worse character than the average person. However I think smart people excel at rationalizing their uselessness. "At least I'm teaching undergrads. At least I know enough advanced math that people struggle to call me out on my shit. At least I protect the environment by refraining from making anything, or doing experiments. At least I write winning grants and fund my graduate students."
I think it's the rare physicist that actually thinks "Yes, this work is useless, but I need a job and will keep up the subterfuge." I think the rationalizations are more common. But this is just my opinion. And consider the context: what's the alternative? Do you realize how hard it is to discover something actually, really new? And the sheer impossibility of doing scientific discovery on a schedule? The expectations are really insane in science. I can't help but think that "professional scientist" is not such a good idea, that we were better off when people did science on the side, as a hobby, and once in a while they'd find something cool and publish it.
There's an implicit assumption here that the "purpose of [physics] research" must necessarily result in concrete results in order to be "worthwhile".
A lot of theoretical physics, at least, is increasingly really mathematics [or computer science] research, that doesn't necessarily directly and simply apply to "real world issues", but that doesn't make it invalid.
(That said: also the majority of physics research isn't fundamental physics research, which is the stuff you're talking about. There's plenty of work in areas like condensed matter physics, plasma physics, quantum optics, etc etc etc that is still producing results and driving new developments.)
I'd say rather that some physicists are doing things that aren't properly called science. Science is only that which can be checked by experiment. This means clearing a space, acquiring tools, preparing the geometry, applying the theory to compute a prediction, and then executing the experiment, taking measurements, and comparing the measurement to predicted measurement. Drop the weight, apply the voltage. Press the button.
Nobody is preventing string theory from being tested. If you know of a way to test it, please go and do so, you'll get a Nobel Prize for it because nobody else has thought of a way.
That's exactly the problem - spending decades studying a theory without any idea of how it could be tested (with devices that could, say, fit into the solar system) is not how science should work.
Perhaps we should simply study other fields, where experiments are at least in principle possible. The ancient Egyptians didn't have to study quantum chomodynamics in order to advance science.
I mean, replication failures are a result of bad science, bad analysis and a poor understanding of statistics in many cases. It's not so much a crisis in the state of human knowledge but the state of the education of the scientists in those other disciplines.
The phenomena are related, though. One could argue that the social sciences, with greater latitude in definitions of measurement and thresholds for statistical significance, had been building sand castles for decades. Eventually, the entire rotten edifice will collapse.
In contrast, the greater restrictions of theory and measurement in physical science didn’t easily allow researchers to do pointless hand-waving that looked good. In some sense, the “crisis” in physics is less embarassing, as it is simply theorists bumping into limits enforced by reality. They didn’t make it up as they went along.
I’m also doubtful the lauded “open science” movement will accomplish anything besides the mass transfer of intellectual property to centralized data platforms, to be mined by replication specialists.
I’m biased, admittedly, after watching an APA zoom conference on the advantages and wonders of open science, and why researchers should join in. The lead presenter’s #1 reason to join open science was “that I didn’t lose my data anymore, it was all nicely and neatly centralized on the OSF server.”
In biology, neuroscience, and psychology replication failure is often the result of an impedance mismatch between reductive models and real systems complexity.
This is an acute problem in animal research where 90% of work gets away with using a single genotype in a single environment. And then the “wise” old heads at NIH wonder that there is a replication bias? Really?
I wish people used the word crisis less and with a more narrow definition restricted to a short time which unexpectedly forces decisions or changes with long ranging consequences, and not a synonym for “shit is bad”.
Crisis sounds so negative. Isn’t this desirable. Ie means there is more to be discovered . I would have thought people in the field would be stoked about the possibilities
Do we know what the pay discrepancy between physics research and computer science and finance jobs. I wonder if we are attracting the brightest minds in high paying jobs.
However, a universe that doesn't have any laws would be an amorphous mush. Forget about planets and stars, it could not even have atoms or molecules - you need an awful lot of stable structure (i.e. laws) to get something as complex as a water molecule out of random particle interactions.
Our investigations ever since the scientific revolution have progressively shown it to be more and more lawlike. It would be a bit of a surprise if this stopped being true.
Yes - I would add that a philosophically-knowledgeable scientist knows that nature does not HAVE to be lawlike. But like you say, the process of science is hypothesizing laws and checking to see if those laws make predictions. So far this process has been very successful.
This is excessively hostile towards a relatively small field in physics. Yup, lots of people have criticisms of string theory and related theories, but the implications that this is all that physics has been doing in that area is very false. Lots of people work on lots of other things and they’ve continually made decent progress, just not the explosive progress which happened at the beginning of quantum physics.
This emotional attachment to certain fields is very unscientific and not at all helpful.
You need to read the article to understand my comment. It is specifically about the crisis in high energy particle physics and cosmology. My comment specifically mentions advances in other areas of physics. In case it wasn't clear, I am saying these advancements, such as imaging and understanding glass (and quantum computers, semiconductor tech...etc), are currently the edge of science and our understanding of the universe. It is progressing, albeit slowly, it just doesn't get any hype like the pseudo-science stuff does.
And my point is, be more charitable to scientists you think are wrong who are acting in good faith. There is a long history of people like this being right despite the oppression on occasion. You want other things to be studied, go help yourself.
There is a long history of people like this being right despite the oppression on occasion.
A dominant school of thought producing no observable results over decades, instead apparently relying on career pressure to conform and perpetuate the path would normally be considered dogmatic rather than oppressed, and doesn't immediately spring to mind as a model for "a long history of people like this being right".
>>>> Anyway, my point is, if someone claims to be a scientist who understands the structure of the entire universe and creation, but can't understand the structure of the windows in your house, they are probably full of shit.
My advice to anybody who is troubled by the apparent certainty of science, is: Get to know some actual scientists. Disclosure: I'm an industrial physicist.
The imaging technique might be cryo-TEM (cryogenic transmission electron microscopy), which is also how we get those spectacular pictures of the COVID virus.
> if someone claims to be a scientist who understands the structure of the entire universe and creation, but can't understand the structure of the windows in your house, they are probably full of...
Isn't that like saying that if you meet someone who claims to know all the rules of chess, but still can't find a way to checkmate Garry Kasparov, they are also full of it?
As Feynman said: It is like a chess game. If you are in a corner with only a few pieces involved, you can work out exactly what is going to happen, and you can always do that when there are only a few pieces. And yet in the real game there are so many pieces that you can’t figure out what is going to happen ... There is such a lot in the world. There is so much distance between the fundamental rules and the final phenomena that it is almost unbelievable that the final variety of phenomena can come from such a steady operation of such simple rules.
The scientists that mrjangles derides, who "claim to understand the structure of the universe", sound to me like physicists claiming they know the base rules of the game. (I'll set aside that nobody has cracked, say, quantum gravity yet).
When we talk about the puzzling mysteries of the structure of glasses, or superconductivity, or turbulence, or so on -- most of those aren't a matter of a lack of understanding of the base rules of the universe, but rather their consequences when applied to a big system with a lot of parts. That's knowing the rules for how rooks work, but being surprised when your opponent captures your queen with one.
Back in the 1960s and thereabouts, physicists liked to believe that this was the case. Since then, breakthroughs in our understanding of quantum mechanics and solid state physics has changed that (particularly in things like super conductivity). Today, it is pretty much accepted that the standard model is really, what is called, an "effective theory".
What this means is that we discovered that the structure and order, as we see in particle physics, actually appears everywhere in nature. For example, vibrations moving through a solid (such as when you tap the table in front of you) actually behave exactly like (what are incorrectly named for historical reasons) "fundamental" particles moving through space. They interact with each other mathematically with the exact same equations. Recently scientists even created a material which these "quasiparticles" (as the excitation are called) obey the laws of special relativity inside the solid, except the speed of light is replaced by the speed of sound in the solid.
All this probably reached its peak when the Higgs mechanism, and indeed pretty much the the entire theory between the Higgs particle, was discovered by P.W. Anderson in superconductors. He suggested that perhaps the same mechanism is what gave particles in the standard model their mass. He was proven correct, but the Nobel prize went to Higgs for historical and political reasons, and also because P.W.A already had one Nobel prize.
Now days high energy particle physics views space as a kind of medium, and the electrons and quarks etc as just being the particular manifestation of whatever chaotic thing is going on underneath (more particles or who knows what), which is meant by "effective theory".
Anyway, the point is that no, it isn't that case of a few fundamental rules are controlling everything. We now have a much better picture and it seems to be order and chaos appearing in all different scales in all different manner of ways and to understand each manifestation one needs to start a new each time.
I've long been a big fan of "more is different" myself, but perhaps you and I have different takes. I think that essay elegantly defines the quintessential nature of emergent behaviour, and the limits of reductionism. But not by refuting Feynman's claim; rather by exploring why it is that when a lot of stuff follows simple rules, the results aren't at all in keeping with the character of those rules, and appear to be better described by rules of their own.
In other words, once there are enough pieces on the board, you get blindsided as your queen is captured by a rook in a move you never saw coming, even though in retrospect you can go back and see that, yes, the rook really did move in a straight line.
That's why, even if biology really is "just" applied chemistry and so on, you'd never predict the wonderful behaviour of biology if you had only studied systems of less than ten molecules.
And I don't think Feynman would disagree at all, nor would he claim that knowing just the basic laws of physics would let you anticipate the character of cell biology or turbulent fluids, or all the other wonderful systems that have nontrivial degrees of freedom.
Ok good point, I think I got side tracked with my comment.
Perhaps a better analogy would be: Someone who claims to be a chess player, but keeps getting disqualified from tournaments for making illegal moves.
For example, when it comes to QCD and the structure of the nucleus, we have no idea if our theories are correct or even make sense. One of the millon dollar Millenium prizes is currently being offered for anyone that can prove the equations of QCD are even well defined or if it is possible to even have a bound state (i.e for particles to exist at all) within a QCD framework.
So my point is the underlying theory is really only described in the perturbation theory setting. I.e., in the high energy limit (smashing things together). Now the equations and mathematics behind QCD are very attractive and probably contain a great many aspects of what we will eventually become the full theory, but until we can predict, for example, the mass of a nucleus from those equations (or anything at all whatsoever), then they are certainly not proven.
So far all we know is that these equations can predict what comes out (and in what direction) when we smash particles together.
It's true that a mathematically rigorous proof that... well... any QFT exists at all escapes us for all but extremely special cases.
But, given you've given a whole spiel about about EFTs, you can think of the lattice formulation of QCD as an EFT whose cutoff is the lattice spacing. We can compute the mass of hadrons and take the continuum limit / cutoff to infinity. And when we take that limit holding some physical hadronic observables fixed, the spectrum matches perfectly. So I think it's relatively unfair and misleading to say that because we can't do it with pen and paper we can't make any low-energy QCD predictions at all whatsoever.
What always drives me crazy about stories like the OP is that strongly coupled theories are automatically technically natural. But most phenomenologists don't like them because they, not being proficient supercomputer programmers, can't calculate anything.
Last I checked the there were enough free parameters in these calculations to make the calculations of less than convincing. For example those 'hadronic observables' make up such a big part of the actual results that what is left over is within the error bounds anyway.
However, that was over 7 years ago, and someone else in the comments linked an article talking about the breakthroughs since then, and they seem significant, so things may well have improved since then.
Regardless, lattice QCD has always been real science and always been quite impressive. Any direct attempt to match theory with known experiments always is real science regardless of whether you agree with the methods.
> Last I checked the there were enough free parameters in these calculations to make the calculations of less than convincing. For example those 'hadronic observables' make up such a big part of the actual results that what is left over is within the error bounds anyway.
> We had back then, and still have, a huge amount of experimental evidence in that field, and no one can explain any of it... so they gave up.
I'm not a physicist, but from the outside, it appears to me the last 10 years have seen a huge leap in understanding the nucleus. See [1]. Or am I misinterpreting that article?
No, because glass isn't a crystal. This is part of why it was such a hard problem: Because the existing sub-molecule imaging techniques couldn't image it.
It's extremely frustrating, whenever a link like this, i.e outside of the IT and programming field, is posted, the number of people, who clearly have ZERO understanding of the subject matter, try so hard to sound smart. It's almost turning HN to another reddit!
To suggest that people like Weinberg was just researching imaginary things is so unbelievably ignorant. Not to mention suggesting that there must always be ONE theory that explains everything from the get-go with no disagreements whatsoever.
Physics/Science has always worked like that: many attempts at explaining a phenomena, after which ONE will be tested and shown to be the "closest" to the truth. And by closest, I mean closest.
I don't even want to begin to address that last abhorrently stupid and ignorant last sentence: "if you don't know the structure of glass you're not a scientist." SHUT UP. If you don't know what physics is, STAY HUMBLE when you comment on it.
> , i.e outside of the IT and programming field, is posted, the number of people, who clearly have ZERO understanding of the subject matter, try so hard to sound smart
It's the same thing with respect to IT and programming articles too, most programming articles that hit the front page have a bunch of comments explaining why the author is the problem with programming today and the technology they're discussing is not useful and all the best shit was invented in the 70s and there's no been no progress since lol.
My comment went from, like +10 votes to -1 and flagged in 1 hour.
Is this your doing or someone else?
I also have a PhD in Physics, everyone I know in my field agrees with me, including my professors. Sorry, but disagreeing with me is NOT a reason to be flagging comments. If it wasn't you then the apologies, I guess my comment is for whoever did it.
since you're in the field, what could be the cause of the "lack of progress" ? We need detector that are too hard to build to get the data/measurements we need to progress ? Or do we lack a sort of "flash" when someone figures the new physics out of the current knowledge by a change of point of view ?
Not parent, but the cause is obvious to everybody in the field: existing fundamental theory (general relativity from 1915 and Standard Model, completed by the mid-70s) while manifestly incomplete, is consistent with all available experimental data.
New accelerator experiments capable of pushing significantly beyond the explored energy range would take a decade+ to build and cost tens of billions (and up), and there is no guarantee that they would find anything new.
Choice quotes:
>We know this both because dark matter is merely a placeholder for something we don’t understand, and because the mathematical formulation of particle physics is incompatible with the math we use for gravity. Physicists knew about these two problems already in 1930s. And until the 1970s, they made great progress. But since then, theory development in the foundations of physics has stalled. If experiments find anything new now, that will be despite, not because of, some ten-thousands of wrong predictions.
>Ten-thousands of wrong predictions sounds dramatic, but it’s actually an underestimate. I am merely summing up predictions that have been made for physics beyond the standard model which the Large Hadron Collider (LHC) was supposed to find: All the extra dimensions in their multiple shapes and configurations, all the pretty symmetry groups, all the new particles with the fancy names. You can estimate the total number of such predictions by counting the papers, or, alternatively, the people working in the fields and their average productivity.
According to her, and many other physicists, there hasn't been any major progress in phenomenology since 1970s when Higgs boson was postulated.
[1] https://backreaction.blogspot.com/2018/11/the-present-phase-...