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In the foundations of physics we haven't seen progress for the past four decades (backreaction.blogspot.com)
237 points by apsec112 on Feb 10, 2019 | hide | past | favorite | 219 comments

I don't think there is a correct answer to the question should we build the next particle accelerator. Its an opinion based on the probability of us finding something (also an opinion) and the relative value of that discovery to $20B.

I got a PhD in theoretical particle physics in 1995. My thesis was about the supersymmetric flavor problem, where we tried to infer information about physics we couldn't measure based on the naturalness criteria she criticizes. My thoughts on pursing this: well, I left physics. I thought it was too hard to make any progress. I went into software. I don't have any regrets.

I shouldn't admit this but I occasionaly daydream in a Walter Mitty sort of way about doing great things. I have had a few physics ideas related to things like quantum gravity that I think about occasionally. Just a few months ago I was daydreaming about me pursuing one of these back in graduate school and it being very successfull. I intertrupted my daydream with a thought, "I'm glad that didn't happen. Then I might have stayed in Physics."

So that is my answer to the question about investing my own time in searching for new physics. None the less, I wouldn't say people are crazy because they think there is some value to pursuing physics as is currently being done.

Another interesting story in undergrad I had a thesis supervisor who was working in cosmology, but had a 20 year career in high energy particle physics (5 as a grad student, 10 as a research scientist and 5 as a pre-tenured faculty member). Basically the moment he got tenure he switched from experimental particle to observational cosmology because as he said "I saw the writing on the wall that after the higgs there was no clear direction for high energy and no clear direction for even finding a way out of the aimlessness." I thought it was kind of crazy that he had a multi-year plan for leaving particle, but I guessed it worked out for him he is now reasonably successful and is a leader in both DESI and LSST. I ended up leaving physics entirely.

Can you expand on why staying in physics longer would have been detrimental?

Not OP, but I have a similar feeling.

I was on my way starting masters on Mathematics when I discovered I would be a father, I had to find and start a career so that I could make ends meet.

From my perspective I am glad that happened, I was excessively ambitious, comparing myself with the great ones in the field, measured my self-worth on regard of my ability to solve problems.

Having to swallow my pride, learn to talk with other people as equals so that I could provide for my family made me a better person. I am not sure I would have done this breakthrough isolated on my intellectual bubble, not even talking about the difficulties of engaging with egos at the academia.

Sometimes I miss the excitement of learning something really difficult or solving some problem from a new perspective, but I am glad I am mentally healthier. I am not saying that it's not possible to be healthy and pursue a high level on Mathematics or other intellectually challenging field, but that can enable bad patterns for some people.

> bad patterns for some people

I have definitely seen that in other people when I was doing my physics undergrad. And to some extent, I probably experienced that myself.

I was on the road to starting a Cosmology PhD with incredibly high aspirations but my (then) girlfriend gave me an ultimatum: physics or me. To be fair, she was the primary bread winner and a graduate lifestyle would have been an even greater strain on the relationship. So, I opted for the latter and went into software. Also, like you, I have no regrets.

I still miss physics incredibly and, you’re right, there is something exceedingly sexy about solving those (including mathematics here) sorta problems. I sort of see it as a way to reach across generations and walk the same paths as the giants have. Anyway, I do find a great amount of joy in software problems, but nothing beats that first love.

> From my perspective I am glad that happened, I was excessively ambitious, comparing myself with the great ones in the field, measured my self-worth on regard of my ability to solve problems.

This is something that I have observed in the sciences: a pernicious, unquestioned, and false great man theory of how science progresses (I wrote about it a little more here: http://madhadron.com/into_the_sciences-sample.html).

Opportunity cost!

Yes, this is it. I became not so motivated in physics. I have enjoyed the work I have done since then more. I missed the golden age of physics but instead have been able to take part in the golden age (to date) of software and the internet.

Do you think the golden age of the internet is drawing to a close?

No, that is why I said this has been the golden age to date. Meaning I think there is much more to come. (So I guess maybe it really isn't the golden age then...)


The current paradigm of particle physics will likely fail after the next accelerator -- everybody abandon ship RIGHT NOW!!Elf!

So since the early seventies there was an interplay between discovery machines, accelerators that prioritize high energy over high precision, and precision experiments. In practice these are proton accelerators, which accelerate to very high energies since protons are heavy, but have the downside that protons are itself very complicated objects, and electron accelerators, that have the opposite trade off, electrons are light and therefore lower energy but are very simple and analyzing the results is therefore very easy.

The way the interplay worked is, that the precision experiments would constrain the parameter space for the next generation of discovery machines, and then the discovery machines would give the next generation of precision experiments a target.

This is to a large extend just research by timetable, and funding agencies love it. Physicists can write a proposal including a list of expected discoveries and funding agencies can then just check that list quarterly.

This paradigm will most likely come to an end after the next accelerator. The next accelerator will be a Higgs factory to measure with very high precision the properties of the Higgs boson.

Now theory did progress a lot in the last four decades, but it closely mirrored this path of experiments and therefore did work within a quite well defined paradigm. That is what she means with "no progress," there was a lot of progress, new calculation techniques, new techniques for model building, the entire effective field theory ideas and so on, but that is all in service of a narrowly defined paradigm.

So it is probably a good idea to start looking for more risky research, because we a pretty sure the boring predictable stuff is coming to an end, but I think that the characterization of "no progress" is a quite unfair characterization of a very fruitful endeavor.

"No progress" really means "no breakthroughs."

At this point physics seems to be in the business of adding epicycles to a model that does some very good modelling, in an epicyclic way, but cannot possibly be complete as a paradigm.

OP's point is that new paradigms are desperately needed, and it's looking unlikely that we'll get them by building a $20bn thing that bangs the same old rocks together a bit harder.

It doesn't help that people who are smart enough to make a difference don't stay in physics long enough to do what they could do. There's more money and less pressure elsewhere.

Collectively, this is not a good situation to be in. Nothing has more potential to change the future than new physics, and CERN-style HEP seems much less likely to get to Quantum Gravity than a new academic and financial paradigm in fundamental research.

What you mean by more risky research?

Just a thought: The fact that there is physics beyond current knowledge doesn't necessarily mean that it's achievable to find out about it.

Think about it: Finding confirmation for the Higgs Boson required building a particle accelerator of 27 kilometers. For the larger part of humanities existence it was probably unthinkable to design such an experiment.

What if the next level of yet unknown physics requires building a machine that's as large as the equator? Or larger than anything that can be built on earth?

I think this kind of issue has always been lurking in the shadows for humanity, not only in physics but in other areas as well. While I'm not certain about the historical details, it seems to me that the ancient Greeks were able to dream up mathematical problems, that resisted solution for centuries.

Similarly, the math required to put calculus on a decent theoretical foundation was unknown until more than a century after Newton's time.

Other areas of science... how do humans think? Can we cure pain without killing people?

Physics experienced an incredible series of lucky breaks over the past few centuries, but each breakthrough doesn't come with a schedule for when the next one will arrive, and we never know when the next one will be a real stumper. We don't know if it will take a month, a year, or a century.

On the other hand, the double-slit experiment doesn't take any expensive equipment, and if things had gone differently, could easily have gone un-noticed until 2019. My bet is there are other experiments like double-slit which will be equally revolutionary and dirt cheap and everyone will be kicking themselves for not discovering them sooner.

> On the other hand, the double-slit experiment doesn't take any expensive equipment, and if things had gone differently, could easily have gone un-noticed until 2019.

This is highly doubtful.

The moment you have "something <mumble> is a wave" you immediately perform an interference experiment.

The photoelectric effect demands a particle interpretation.

The combination of the two in a double slit experiment is almost immediate and obvious.

We went from Millikan in 1913 determining the charge on an electron to DeBroglie hypothesizing electrons also having wave/particle duality in 1924 to the Davisson-Germer experiment in 1927. That's really fast given the technology of the day.

So why did it stall? Apparently death by committee at the Solvay Conference with the insistence on an indeterministic paradigm.

I've been having a field day learning about pilot wave theory and recent (this century) research that helps empirically visualize it. David Bohm had quite the mind.

> So why did it stall? Apparently death by committee at the Solvay Conference with the insistence on an indeterministic paradigm.

Not completely. Some of the issue is actually the technology available at the time.

Einstein (who propounded a fields explanation for things) vs Bohr is the great debate and Bohr won.

The problem, at the time, is that Einstein's formulations predicted certain things. For example, if Einstein's fields formulation is correct, you don't have electron levels that decay. And that's clearly incorrect.

Except ...

It turns out that the better and better you isolate an atom, the longer and longer it takes for its electrons to return to ground state.

So, Einstein was correct, but it's only been in the very recent decades that we can create isolated, single quantum state systems which we can probe.

Physics is often constrained by the technology of the time. How long did it take until Einstein's predictions were finally tested and confirmed?

Look at how much engineering it has taken to bring the Kibble balance up to enough accuracy to become the new kilogram standard.

I want to agree with you - if for no other reason than the current research path seems impossibly complicated. Needing to cool things down to milikelvin or building megastructures is restrictive.

I strongly suspect that there are some experiments that can be done similar to the Cavendish experiment which could prove the Quantized Inertia theory, and might even get a share of a Nobel prize. They could be done in a garage, with some cheap electronics, servos, and a raspberry pi or two.

> What if the next level of yet unknown physics requires building a machine that's as large as the equator? Or larger than anything that can be built on earth?

Then we need to fund that engineering.

That's part of the argument. Will a bigger collider really be the best use of funds?

Pouring enormous sums at, for example, the solid-state physics of superconductors and figuring out how to make an actual room temperature superconductor could advance many things simultaneously. (For example: room temp superconductors probably enable fusion at reasonable scales--and fusion at decent sizes gates most megascale engineering projects. Another example: quantum computers have several open questions about them that may mean that they never achieve generality--we should probably probe that intensely).

Nobody is saying to never build another collider. But the real question is "Do we have a good reason to build another collider right now? Or should we shunt that money elsewhere in physics?"

So what? If we don't take steps forward we will never get anywhere. We can only operate with the best capabilities and knowledge available to us today.

$20B is nothing compared to the world's GDP. If there aren't more compelling research projects of similar magnitude in fundamental physics, then we should build it. Of course, I'm not qualified to make that judgment, but I think we have good reason to trust that smart and reputable people are working hard to make the right call.

We should always be investing a proportion of our accumulated wealth and resources into exploring the unknown and making scientific discovery.

This a very simplified way to look at the original post, glossing over most of the details and missing nearly all the points.

Nobody is arguing against spending (lots of) money for scientific experiments. The problems that arise are qualitative rather than quantitive. As the original post outlines, there are many experimental domains one could allocate that money towards. One of the issues is that of cutting your losses. When does one accept that enough is enough and starts doing something else? Smart and reputable people are not infallible or less prone to making terrible (self-centered, ego-driven, profit-seeking) decisions.

One of the points that the original post is making is that high energy physics is dominated by these kinds of people. Predictions repeatedly invalidated yet still clinging to the same ideas. That is starting to look more like a religion or mania than science.

the purpose of the LHC was not to find the Higgs boson, but to keep probing matter at higher energies to find whatever is to be found. It is not particularly smart to brute force stuff but it is a rational choice unless one can propose an alternative. It is the default choice considering the options, and i believe there is a hope that given enough time something useful may be produced as a side-effect (I mean, the WWW was not a bad perk). The next level of physics may not have to do with higher energies but with bird droppings again.

There's another, more simple, explanation. We have made some fundamental mistake which, due to its 'naturalness' was adopted as all but a certainty. You reach some point that trying to build upon things becomes impossible when your foundation is fundamentally broken. For an example of times past, just consider the geocentric vs heliocentric universe issue. The geocentric universe (that Earth is the center upon which everything else revolves) was fundamentally built upon a model and assumed to be correct. This means that any sort of 'weirdness' that emerged from it was not really a problem but instead just massaged into the model itself.

As a couple of examples of this consider the fact that a geocentric universe means the planets that orbit us must travel in these really peculiar swirly type patterns. This happens nowhere else in nature and doesn't really make any physical sense, but when you assume a model of a geocentric universe it's not really a problem - you can just massage it into the model. Another example of a very bizarre oddity that would be seen nowhere else was in things like Mercury suddenly having to stop and start going backwards in its orbit. Again this is not seen anywhere else and doesn't really make much of any physical sense, but if we take a model as reality - then sure, you can massage it into it. Why not?

These lead to the real problem. Model based science is a really bad idea, because it's really hard to falsify models. In the case of the geocentric universe it ultimately required being able to see the starts 'through the eyes of god'. A good deal of physics today is built around models. And as these models have absorbed more and more 'oddities' they've started to be seen not as models but as simple reality whose proof is but a mere formality. And as is the case with the geocentric universe, you reach some point at which time further discoveries start to seem ever more elusive. Imagine trying to research orbital mechanics when you start with the assumption that planets travel in 'swirlies' and some can even stop and go backwards!

As this articles mentions, modern physics adopted some very substantial changes to the model of universal thinking in the 70s. And those adoptions have now, though unproven, become defacto 'reality.' Yet since then, there's been nothing. And maybe one of the worst problems with models is that they can be completely wrong but you give you valid answers. For instance you could (and can) determine the orbital periods and locations of planets using the geocentric model. And that was done for more than 1500 years! It was incredibly complex, but it was possible. That, in turn, could then be used as 'proof' of the model's correctness, when in reality it was anything but.

We have made some fundamental mistake...

I was just thinking about how Schroedinger 'worked up' his famed equation. A physics historian told me (not in these words) that he didn't actually 'derive it' but sort of ... 'arrived at' it.

The WP bio says that in his fourth paper on the subject (which first involves time), he greatly simplified the -equation- by introducing complex numbers ... and then:

"something magical happened, and all of wave mechanics was at his feet.... Schrödinger was not entirely comfortable with the implications of quantum theory. He wrote about the probability interpretation of quantum mechanics, saying: 'I don't like it, and I'm sorry I ever had anything to do with it.'"

Introducing complex numbers -made the equation more beautiful-. The equation e^(i*pi) = i^2 is amazing, but may also suggest that we're not looking at the math's basement level.

It's been suggested that all of the pyramids' stones couldn't have been cut with two-foot-long copper saws. It may be that the 'beauty' people are seeking is limited by their tools, as much as their imaginations.

> It's been suggested that all of the pyramids' stones couldn't have been cut with two-foot-long copper saws.

Pyramid stones are made of concrete and cast in place. It's very primitive technology, which is known for few thousand years.

The pyramids were not made of concrete. They were built from sandstone blocks and clad in limestone. and the stones were cut using stone tools, not copper. Copper is too soft for stone working but quite a few rocks are harder than sandstone.


The pair believe that the concrete method was used only for the stones on the higher levels of the Pyramids. There are some 2.5 million stone blocks on the Cheops Pyramid. The 10-tonne granite blocks at their heart were also natural, they say. The professors agree with the “Davidovits theory” that soft limestone was quarried on the damp south side of the Giza Plateau. This was then dissolved in large, Nile-fed pools until it became a watery slurry.

Lime from fireplace ash and salt were mixed in with it. The water evaporated, leaving a moist, clay-like mixture. This wet “concrete” would have been carried to the site and packed into wooden moulds where it would set hard in a few days. Mr Davidovits and his team at the Geopolymer Institute at Saint-Quentin tested the method recently, producing a large block of concrete limestone in ten days.

http://www.ce.memphis.edu/1101/interesting_stuff/pyramids_in... https://www.geopolymer.org/archaeology/pyramids/are-pyramids...

This is very far from accepted and is thoroughly refuted here


Accepted by whom? Information about ancient concrete and other types of cementation can be found in various books, e.g. [1].

I saw picture of cement klin (oven?, non-native speaker) in Peru, built more than thousand years ago, which looks _exactly_ like freshly build cement klin near to my home (Rivne, Ukraine), but labeled as "an ancient temple, filled with dirt".

[1]: Lea's Chemistry of Cement and Concrete

Concrete is a science of its own- it is not so simple at all.

Yep, so it's why it was forgotten so many times in history.

You can make naked eye observations but it took the telescope (and more accurate time keeping) to have accurate enough measurements for an actual proof. Multiple ancient Greeks who had strong arguments for Heliocentrism, but there wasn't enough empirical evidence. That took Keplers Laws and a telescope. It could not have been proven without the necessary level of technology.

The same is true today. Except we know our theories are incomplete and in many cases we know under precisely which conditions it's incomplete. We simply can't access those energy levels to reach the next step yet. We also know constraints on what can be possible while keeping most of what we think is true, we lack the ability to go further than that however.

So we are waiting for the technological breakthroughs to prove or disprove our many candidate theories. It's like Kepler waiting for Tyco's telescope data. We can't rule things out without stronger accelerators or radical ideas that are actually testable.

Geocentric vs heliocentric universe issue is an interesting example, because the geocentric version is not actually wrong, the whole point of the general relativity principle is that it geocentric an equally valid viewpoint.

The trick was understanding that circles+epicycles around earth are in fact equivalent earth and everything else rotating around some other point. Which is a relatively easy insight with analytical geometry, but is hard to see without it, and people noticed it only after they had more detailed data, and had to describe epicycles for ellipses instead of simple circles.

So if this teaches us something, it is that most likely we already have all the data that we need, we just need to look at it differently. But to look at things differently we need more math, and more experiments.

The Relativity of Wrong is worth reading here. No one proved heliocentrism without first showing they could recover the epicycles from the heliocentric model.

The funny part is, both geocentric and heliocentric is wrong. The sun and the planets all rotate around the barycenter. None of them is special.

The orbits being ellipses instead of circles, center of mass being different from center of sun, precession because of general relativity effects, are all small corrections, and as described in Asimov's relativity of wrong suggested by the sibling comment, they only add detail to the picture. The question of geocentric vs heliocentric is different, because it is about looking at the same data in a different way. All the corrections can be added in geocentric model as well, but everything looks much more complicated in it.

It is very similar to the formulation of classical mechanics in terms of least action principle. Both formulations make the same predictions, but least action principle leads to a simpler formulation of quantum mechanics: Feynman's path integrals.

You need the same corrections in a true heliocentric model as well, they are just smaller. The true leap in understanding comes when you realize that none of the objects is special, none of them is the true center, they all follow the same rules. That's where the simplification of the theory happens.

Well, 'models', or concepts in general, have been seen as flawed for many centuries when it comes to apprehending reality. Sadly, there's no other game in town.

It's also really questionable if another game could make logical sense. Kant's stuff on speculative reason comes to mind.

Well this is why we have Occam's Razor: If two models make the same predictions, but one is simpler, then we use the simple model. You can make accurate predictions with a geocentric model of the solar system, but it will be incredibly complex, whereas the same predictions are made much simpler by a heliocentric model.

If you can create a model of physics that makes predictions matching what we've already verified, and it is simpler than the Standard Model, then I'll bet there's a Nobel in it for you.

> What if the next level of yet unknown physics requires building a machine that's as large as the equator? Or larger than anything that can be built on earth?

Well, one thought is that we already have access to much higher energies - via cosmic radiation.

Of course, a lot about that radiation is uncontrolled, which makes things difficult...

There's much to be done with lower energy experiments, including understanding the weak nuclear force and possibly LENR.

For anyone else who had to go look it up, LENR is the new name for cold fusion.

LENR is a much better name for a still little-understood phenomenon.

From the NASA archives:

"Low Energy Nuclear Reactions is a source of thermal energy. It is an immature technology that requires further research to determine the best propulsion system integration on a vehicle platform. LENR has the highest specific energy of the alternative energy sources mentioned at about 51,000,000 Wh/kg.3

This is a conservative estimate from the recent LENR reactor test that was conducted in March 2013."


I'm beginning to think governments are afraid of LENR for a couple reasons. One, it would disrupt the balance of power in the world on multiple levels. And two, it may turn out that nuclear weapons could be built cheap and easy. That later thought is frightening.

If by governments you mean people who are tasked with thinking about the negative implications of policy and technology on other human beings and (hopefully) opting to act in ways to minimizing negative consequences for society while balancing the needs and human rights of people, then yes.

This is conspiracy thinking unfounded by evidence. Nobody is scared of "LENR" and if the research surrounding it had even a little credibility then it would be the #1 national security concern for every 1st world nation.

Why would it be a national security concern?

Because such a fantastical technology would have gigantic military and economic implications for any nation in possession of it. If any credible researchers could demonstrate a plausible path towards such a discovery scientists would be up to their eyes in DARPA research grants.

True, but I'd also posit that such research would be kept out of public view for exactly the reasons you stated. That means all we'd be seeing is the half-baked approaches by people who don't quite get it and can't seem to get high quality, useful, and reproducible results.

Or instead of upping the size dimension, perhaps exploiting some relatively newly discovered phenomenon to continue the exploration.

So, yes, aside from the discovery of neutrino mass there was no "fundamental" progress since the Standard Model -- as in, all the effects we see in current experiments are accounted for by the theory -- if you know how to calculate them well enough, which is actually not trivial at all, and has been keeping physicist busy for the last few decades.

And yes, by scientific standards 20-30B EUR over ~25 years is a large sum, even though 1B/year is about the current CERN budget, about 1/5 of the current ESA budget, 1/20 of NASA budget, and 1/500 of the US military budget, etc -- so not that outrageous by other standards.

And yes again, there are multiple cheaper experiments with a more certain outcome. For example the Japanese Hyper-Kamiokande neutrino detector will provide enough data to solve neutrino mass hierarchy problem at the cost of ~2B EUR; or the space-based LIGO successor, LISA, which will improve over LIGO's ability to detect gravity waves by half of a dozen orders of magnitude for about 1B EUR or so.

And yet, those experiments can not bring more understanding into the "fundamental" physics -- i.e. to find a breach in the Standard Model. Only two kinds of experiments can:

1) cheap detectors constructed to test special classes of SM extensions (e.g. detectors like ALPS, which consist of a laser pointing at a wall to search for e.g. axions) -- if by some luck the particular extension turns out to be true;

2) a collider with higher energies like FCC, CLIC or ILC.

Now, there's no shortage of the cheap experiments, but up till now they've only excluded certain classes of "beyond standard model" theories, while confirming the SM even more. We'll probably continue building these in the forseeable future, but overall it doesn't seem likely that we'll find anything here.

So if you want any progress in the "fundamental" physics -- there doesn't seem to be a way without a bigger collider to show deviation from the SM. Without such an experiment, all people are left with is speculation, and that is how you get the string theories, supersymmetries, and the dreaded "naturalness" criteria, which the author of the article dislikes so much.

Right, there is a reason to build ever-larger colliders. The question is: is it worth the cost? And, really, what's the opportunity cost? If a new collider costs ten times what experiments like Hyper-Kamiokande cost, if building a new collider would crowd out the smaller experiments, then maybe it's not worth it.

But before we had better reasons to want to build larger colliders: to observe more of the SM particle zoo. Utimately it was to observe the Higss boson. If the SM has run out of predictions we can only test with bigger colliders, and the only reason left to build bigger colliers is to test SM more finely, or to hope for a break in the SM, well, these reasons aren't quite as compelling. I think this is TFA's author's argument, and I don't think it's wrong.

We might still decide to build a bigger collider, but we should admit that the arguments for it are not that compelling.

We have here someone who doesn't/never work/ed on HEP but on something so remote from it that I would find it hard to even call it physics sometimes. She goes on a sudden crusade against HEP and all its (prominent) practitioners who spent years working on it. She uses some facts we all agree on (uncertainty about the future, etc.) then twists them in a way that makes it look as if the whole HEP community is part of a huge conspiracy to deceive the public. Our truth warrior then courageously exposes them in her ... blog. BS.

On the other side how the hell can she justify her salary and grants to taxpayers? Why isn't she doing some biology or something? It's all so incoherent.

I used to read her when she was less crazy. But I really can't stand her anymore ... it's just too much.

It's all very strange. Two of the most popular and active bloggers in HEP are totally crazy and politically extreme (although in opposite extremes). Blogging seems to be an unhealthy activity for physicists.

This is an ad hominem attack that doesn't really help us understand whether the core substance of her argument is true, which is what really matters.

which is what really matters

Says who? This isn't a debate and you're not the debate moderator.

For my money, interesting things about the author are absolutely on topic. They help us put what we're reading in context.

And opinions are okay here too.

With apologies for Appeal to Authority: Paul Graham elucidates the low value of Ad Hominem in his post How To Disagree: http://www.paulgraham.com/disagree.html

It's not as though the author's biases or background are completely irrelevant; but discussing them is unhelpful without additional clarifications on the mistakes, ignorances, or dishonesties alleged.

Imagine a different context: maybe I have a strong opinion as a lay citizen on campaign finance issues. It's all well and good for someone to enter saying "I'm a political operative/lobbyist/etc, and you don't know what you're talking about"; but it's a zero-information statement until they describe what they know that I don't (which would be just as helpful and pertinent if I had turned out to be an expert anyway).

> but it's a zero-information statement until they describe what they know that I don't

I don't think it's a zero-information statement at all. If S. Weinberg tells me that my physical arguments are wrong but he doesn't have the time to say how/why, then it's certainly a non-zero information statement and I'll scrutinize my line of thoughts thoroughly after that. Dismissing this as a zero information statement would be pretentious from my part. The same goes for you against the expert in political finances.

It seems that there's an underlying assumption in your argument that we're all equal and equally capable of having opinions on anything unless someone comes to us, and spends time thoroughly showing us why we are wrong. Or that we are all correct until proven wrong. This is problematic because 1/ we're not all equal, and acknowledging that we dont know everything is important, 2/ it's unlikely that there's always an expert around willing to spend time educating us everytime we feel the need of commenting on things we dont know, and 3/ we may not comprehend why we are wrong by lack of proper education.

I’ve heard a lot of the terms from that post but never read it. it’s extremely awesome and thanks for sharing. Was particularly inspired by this line:

You don't have to be mean when you have a real point to make. In fact, you don't want to. If you have something real to say, being mean just gets in the way.

>This isn't a debate

It's a public discussion of an important matter, and these tend to go best when people present arguments based on their positions. When someone like you fails to do this, then I tend to assume that it is because they lack such.

edit: here is a link from below that is an example of such an argument: https://slate.com/technology/2019/01/large-hadron-collider-f...

I don't see a thorough debunking to be honest. The first commentor points to the practical results of particle accelerators. The Vox article (and the blog author) acknowledge this fully. But all examples that are given are the result of past accelerators, where we had reasonable expectations to find new technology because we were still exploring the standard model. This is not the case for a larger accelerator, and this is Hossenfelders point.

The second commenter follows a similar logic. He doesn't seem to engage the point that we don't expect the discovery of something new, he seems to suggest that scientists should build bigger accelerators simply because we can.

But he must know that this is not how science works. Chemists don't just simply perform all imaginable chemical reactions just to completely map the space of chemistry. We allocate scarce resources like time and money to experiments that, according to our best models, may yield promising results. We have ideas for experiments like this in physics, they just happen to not involve a larger accelerator. Scientists are not blind cartographers.

That is not at all how science works. Models yield predictions about the world, not "results" as you suggest. We design experiments to test if those predictions, and thus the models, are correct. Often, new "results" are found when a model fails, and that is why we test boundary conditions.

There is no way of predicting which line of work is likely to yield new physics as you suggest there is.

Neither of those twit sequences directly address the points made. Yes, a larger collider would probe the Higgs field with more precision. It would lead to more precise measurements of what is already known. The question at hand is "is it worth 20 billion dollars"? And if it is, why are all the press releases surrounding the proposal hyping up new physics?

The first link is not very compelling. Nobody disputes that particle physics has produced useful derivates for humanity in the past. The question is whether it will in the future, and whether they will be worth $20B.

> Blogging seems to be an unhealthy activity for physicists.

This kind of observation is valuable, I think, even if it's only statistically true. Certain disciplines encourage practitioners to work within conventions and with capabilities that closely match the activity of blogging (or being on Twitter). For other disciplines, tweeting/blogging is very far from the core competencies, so practitioners who do pursue it are more likely to be outliers.

The other, not-so-neutral aspect of this is the narcissism problem. People who do a lot of personal PR are more likely to be narcissists—and this is a more negative indication in disciplines where self-promotion is an anomaly.

I agree. I've come to the same realization recently when I started following the work of some CS researchers. I was (and still am) amazed to see how active they are on the internet (here, twitter, medium, youtube, github, blogs, etc.)

In the far more conservative physics community, there are (essentially) only two ways of communicating that are acceptable: writing academic papers, or delivering academic talks. Online presence is seen with suspicion.

I am not sure if this is a good or a bad thing.

>People who do a lot of personal PR are more likely to be narcissists—and this is a more negative indication in disciplines where self-promotion is an anomaly.

Spot on.

In my experience many of the CS people who are most active are basically doing it for career visibility reasons and much of what they post is either highly misleading or exaggerated to the level of clickbait. But it depends who we are talking about.

I was thinking specifically of the AI/ML folks. Many top researchers from universities, google, open ai, fair, etc. are super active online. I don't think they do it for career visibility.

There's a cargo cult blogging thing going on in ML, where you also have a large number of tutorials written by variably-competent people written not to inform, but to look good. As I'm sure you know, the results are fairly mixed.

>much of what they post is either highly misleading or exaggerated to the level of clickbait

Could you give some specific examples of each, name some names?

Sincere question: what’s crazy about her article? It seemed pretty fact-based to me, and I don’t understand what she was twisting.

For a reasonable rebuttal of her arguments, please take a look at this article on slate [1]. The main argument against her article is that progress in science is not just measured by how many particles you've discovered this year. (disclaimer: former HEP physicist here)

[1] https://slate.com/technology/2019/01/large-hadron-collider-f...

That article is nowhere near a rebuttal of Hossenfelder. It makes a semi-decent case that the LHC was not a failure, which no one is disputing AFAICT. It doesn't even attempt to argue that a new, bigger accelerator is a good idea... unless you count the mere juxtaposition of the hypothetical new accelerator with the non-failure of the LHC, which is a despicable, manipulative form of persuasion.

Then there's this:

> Finding out that there are no particles where we had hoped tells us about the distance between human imagination and the real world.

Which is Not Even Wrong. It sounds like it was generated by a Markov bot trained on quotes from Neil deGrasse Tyson.

Yes, and that she has a book to promote with the same thesis doesn't help matters... It makes it look even more like a selfish cry for attention and ultimately money. She has something interesting to say, but to say that the Higgs Boson measurement was somehow well predicted is... odd. One could also make similar arguments against the Gravity Wave observatories, but now that we've actually seen (and continue to see) events, that is silly.

Really, there was a golden age of particle physics when it was easier to theorize and find things. Maybe the allocation of money should be different, but that has more to do with politics and how governments make funding decisions. How do they view the benefits of what we learn building an LHC, collecting, and analyzing the data? You can argue about whether those benefits matter to physics... but Tim Berners-Lee had to work somewhere.

Gravitational wave observatories are not the same thing at all. They're a new kind of telescope, and new cosmology and astrophysics results are going to keep coming in. Confirming yet another prediction of GR is icing.

Two of the most popular and active bloggers in HEP are totally crazy and politically extreme

May I ask who the other crazy person is?


I would second your observations. The blog seems to whining about things without substance or any constructive propseal. It even runs the risk of bashing those who dedicate their life in exploring nature. It is stromgly recommended that the German lady think more maturely ...

Well, maybe it isn’t worth spending another 20B on a new particle accelerator, but if so how should we continue? Smashing particles together at high energies is at least a proven strategy that has yielded results in the past and I personally don’t know how we would do high energy physics without them? Maybe we could think of finding ways to investigate naturally occurring particles at those high energies (e.g. via cosmic radiation) but that seems more sci-fi than reality and also won’t cost less than 20B I would argue.

Also, not making progress for 40 years is not really long, we just tend to view everything relative to our own lifespan and we were also pretty spoiled with the marvelous discoveries we made in the last 100 years, but it’s entirely possible that we have now worked out all the “easy” stuff and that making further progress will take 1000s of years (though I think that’s unlikely).

>Smashing particles together at high energies is at least a proven strategy that has yielded results in the past and I personally don’t know how we would do high energy physics without them?

Isn't that a little cyclical? Why should we do "high energy physics" as opposed to just physics? Aren't there other ways to come at fundamental particles than smashing things together and seeing what happens?

>Also, not making progress for 40 years is not really long

Compared to the previous 100 years rate of progress, which was the baseline, it is huge.

That’s what I said, making tremendous progress in the last 100 years doesn’t mean we will continue making progress at the same rate (though I hope it’ll be the case or that we actually accelerate our rate of disclvery). There are good ways to learn about fundamental physics apart from particle accelerators, but for investigating the structure of matter in a systematic and reproducible way there aren’t many alternatives as far as I know.

> Compared to the previous 100 years rate of progress, which was the baseline, it is huge.

That's kind of cherry-picking, isn't it? 1850-1950 basically rewrote the sum of human knowledge when it comes to physics. That isn't a "baseline", it's a major breakthrough.

>That's kind of cherry-picking, isn't it? 1850-1950 basically rewrote the sum of human knowledge when it comes to physics. That isn't a "baseline", it's a major breakthrough.

And we're at the end of the sigmoid curve of that breakthrough...

Exactly. So maybe it makes sense to reallocate some resources to concrete applications of what we already know, but it still isn't fair to expect basic research to make the same kind of progress today that it made in the 1900's (the decade, not the century).

Let the universe provide the high energy particles. Biuld big detectors, not accelerators.

And telescopes to study objects like quazars that too are just sitting there demoing high energy physics 24/7.

3000km^2 in Argentina: the Pierre Auger Observatory (http://auger.org) for ultra high energy cosmic rays.

It was meant to get a follow-up 7x the size in Colorado but it was defunded by NSF as a result of the 2008 crisis.

The exciting prospect of this was that at extremely high energies of cosmic rays (where they get very sparse: 1/km^2/century), these charged particles have a relatively short range (in astronomical terms - they're not from our galaxy; look up the GZK effect). That meant that they wouldn't be deflected by magnetic fields as much and could - thus the intent - be traced back to their sources. The clou: we have no credible theory for any process that would put this much energy into a single particle, so knowing their sources would be a step towards solving a physics mystery.

Source: worked on my PhD there.

PS: Pertinent to this thread. The Pierre Auger Observatory cost around 40M$.

Sure I think we’re already doing that, but I also think this makes it very difficult to observe results let alone make controlled experiments. I can’t recall any particle or fundamental force that was validated / found in this way, the only thing I can think of are tests of the theory of general relativity that use astronomical observations, but I don’t recall anything in the field of particle physics (it’s not my field though so I might just have missed it).

Going much further in the past, you have the discovery of the element helium, whose existence was predicted by the periodic table, and it was detected first in the sun atmosphere (looking at the spectrum of sunlight during an eclipse) than on earth (where it is very abundant, but mixed with natural gas).

Counterexample: discovery of the positron in cosmic radiation https://en.wikipedia.org/wiki/Positron#Natural_production

> I can’t recall any particle or fundamental force that was validated / found in this way

LIGO? Gravity waves?

That’s what I meant with tests of general relativity. Ligo didn’t prove the existence of gravitons though.

Before particle accelerators, we had physicists climbing mountains and pointing photographic film at the skies

The hunt for dark matter, for whatever particle/string/widget is involved, is a particle physics problem. String theory may find support, or not, through the observation of black holes (ie fuzzball).

Neutrino detectors made big contributions in thier day.

If you look at the history of science over the last 2000 years or so, new insights have popped up from time to time in a rather random way. There isn't really a reason to expect them regularly thought that doesn't mean we shouldn't stop looking.

>If you look at the history of science over the last 2000 years or so, new insights have popped up from time to time in a rather random way.

In the last 2000 years yes. In the last 250 years, no, there was a constant barrage of new insights.

This is what has changed for the last 4 decades.

It's also worth mentioning that around 90% of all the scientists that have ever lived are alive today [0]. And not only that, but you could probably fund all of the science from 1900 and earlier with the budget of just one of the mega-experiments (ligo, LHC, ISS) of today.

[0] https://futureoflife.org/2015/11/05/90-of-all-the-scientists...

There wasn't a constant barrage of new insights in every single field throughout the past 250 years. Individual fields most certainly had periods of slowed or stalled progress.

>There wasn't a constant barrage of new insights in every single field throughout the past 250 years.

Which is neither here not there, since we were talking about specific fields such as physics that did have a constant barrage.

Lem's Summa Technologia is a fantastic philosophy book on exactly this subject. He talks about how our racial destiny starts to be controlled by external forces like the chaotic nature of technological progress and how we have less control over our future than you might expect. Dense material but really rich with things to think about.

Agreed. In the meantime, because we don't have understanding about something yet, it doesn't mean understanding does not exist because we don't understand it.

Many of the brightest phds in today's society are working on platforms to gather and retain people's attention to get clicks on ads. Maybe this is part of the reason.

Reaching children with education who don't have access to it will bring more of this random forward progress.


With all the technology we have now and the web and where it's gotten to it amazes me that education hasn't been revolutionised.

Example, I was interested in doing a BSc/B.Eng in software engineering online only (in the UK) and it was silly how difficult it was to find out basic details and pricing.

If I were in a different position in life, which is to say one where I had the wealth and influence to pull it off, I'd have started a non-profit for educational games. I think there is a lot of potential there that was largely untapped because the people who make decisions about what to buy had an inherent bias against anything fun; perhaps reasoning, on some level, that if it was fun it couldn't be educational, that learning had to be boring and awful because that's how they remember it.

But then I see games like KSP, which are engaging and interesting enough (downright fun enough) to drive people to learn about orbital mechanics. Not because it was on a test, but because it was a tool that could get them get to Duna. Or Minecraft, which can teach critical path analysis and Boolean logic. There's a lot of potential in games to present you with a goal you want to attain, and allow you to discover the usefulness of any given subject as a tool to achieve that goal.

Instead we get this "gamification" of education, which essentially means using the nastiest tricks of the F2P market to make kids do their homework. Bonus: we can sell you tablets!

There's no particular reason it needs to be non-profit. School books, for instance, are sold for profit, at substantial markup, by private companies. Does make one wonder why there is (to my knowledge) not much of a market there.

The textbook industry is horribly corrupt and produces crappy products. I want the mission to be enhancing the quality of education for everyone, not making shareholders money.

Textbooks are definitely a spooky world. Open textbooks and open educational resources are an interesting idea - institution pays profs to write a book instead of the publishers.

A lot of the issues would seem to be human behavioural and social stuff rather than the actual information. I mean even before web tech you could in principle learn the vast majority by reading books but most people lack the motivation. And then you think you might just be able to do the exams but a lot of university qualification is just certifying you've been in the vicinity of lecture halls for 3 years or so rather than the actual tests. I'm sure there must be some way to do better.

Oh I agree its cultural.

Just seems strange that an online degree/masters costs the same as in-person one.

I'd have been quite happy to teach myself the entire syllabus, what I really want is them to certify via the exams that I've learnt the stuff.

Of course if they ever actually do go that route they damage themselves economically.

Universities have had the exclusive market for higher education cornered for what a millennia or so.

Technology is easy, but education is about human beings, and I don't think human beings are fundamentally any better understood today than they were by the ancients.

This is an area I'm working in. It's interesting why education disruption has been delayed, but that is finally starting to get on the radar.. :

- Academia believes they own knowledge, curriculum and delivery, when they are losing relevancy in all 3. They haven't kept up.

- The rate of change in society has surpassed academias ability to keep up. Calculus and traditional topics do not change every 2-3 years, but disruption does.

- The 2000 year old model of lectures and seats in butts is changing with, or without institutions. Recording lectures and surrounding it with questions is the height of what we have, and hasn't changed since the 90's.

- Academics largely are not competent with technology but try to implement it, or oversee it. Academics also don't professionally learn how to teach, unlike teachers. As a result, teachers of k-12 students are more tech literate than their post secondary lifers, and the wave of k-12 students heading towards post secondarys that have a worse digital learning experience than their schools.

- Employers hire competency and not just education alone. Curriculum is outdated often by the time it's released in more and more industries.

- While self directed learning is growing into many professions, instruction needs to evolve. I don't believe instructors can be replaced, but they need new and better digital supports.

Don't forget:

- Powerful factions in government find an educated populace threatening, and are taking concrete steps to respond to the threat.

That may be one of the more difficult problems to address, just because it's self-sustaining.

According to Bryan Caplan (writer The Case against Education) the value that academic institutions provide is not necessarily knowledge but ranking the students in order of their perceived competency for jobs.

As far as that remains true I see little to no hope for any displacement of "The Academy" from its current position of significance.

There is some question whether for emerging or rapidly evolving positions employers hire competencies over academic badges.

Wise institutions are working on this but the average rate at which they react may be a challenge.

I've been programming as a career for a long time and gone up against candidates with degrees and been hired where they haven't so there are a fair few companies out there that don't care.

That said I'd like to do something academic and I'm getting older and given the ageism in tech a degree/masters might tip the balance.

Mostly though I just like learning and if I'm going to do it anyway I might as well look to see if I can get more than just gratification out of it.

Your second point is a recurring thought I have every few weeks as I trudge through grad school and it's depressing to think about how much talent, even among undergrads, is ultimately used for consumer services or moving money around.

I hope we can afford to pursue other things one day soon too. The tech I grew up with and hang onto today is not about creating wealth, but creating value.

There will be a world of interest and attention to build for if social media doesn't evolve and people do.

Yes, but 250 years ago one bright guy with a blog used his genius to get people to click on text ads — and he did more to advance physics than every living PhD with their billions of budget in the past 50+ years.

Dear driveby downvoters: instead of burying this mirror of a comment, why not engage? The positive discussion below has room for your perspectives too

I don't have any sense for how much the author is contributing to any discussions of worth -- but I do struggle with the phrase 'foundations of physics'. To me 'foundation of' invites comparison to similar uses in other domains -- in math where it tends to concern the nature of argument, or to computer science where it concerns mechanisms for accomplishing defined goals efficiently or reasoning about program performance/semantics, or to engineering where it concerns such things as stacking rocks and balancing forces so as to ensure that a given way of stacking is probably capable of lasting for a certain amount of time.

But why exactly should 'high energy physics' be considered more 'foundational' than other domains of physical observation? Particle physics pursues description of effects that can occur at very small sizes - but are there _really_ such tight linkages from the observational domain of particle physics to observable 'larger scale' physics such that one truly deserves to be labeled 'foundational' for the other?

Just to pick a domain out of a hat, when modeling things like electromagnetic potentials in material science, actively investigated theoretical models are coarse grained so far beyond the scale of the probing done in particle physics that I have wonder how much are the 'foundational' theories and the larger scale ones ever really expected/required to be consistent with each other ...?

If 'foundational' isn't a statement about the direction of the consistency requirements the components of argument - then what exactly is it a statement about?

As long as you hold onto the assumption that all physical phenomena on the macro scale can in a (perhaps not useful) sense be explained reductively by particle/field physics of some sort, it's clear that poking at the particle/field/whatever substrate is more foundational than studying high level emergent phenomena. That isn't to say that high-energy particle physics is the best or only avenue of fundamental exploration; obviously, much of the last century's advancements came from cosmology.

There's nothing wrong with studying condensed matter physics, and there is a huge amount to learn. But I don't see a conceivable way in which discoveries made by studying complex behavior closer to our scale will help solve quantum gravity or dark matter.

Then again, if humanity were one big game of Civilization, I'd be directing my tech tree towards engineering and applied physics research at the moment: we probably don't need any more fundamental physics to build sustainable fusion reactors.

> But I don't see a conceivable way in which discoveries made by studying complex behavior closer to our scale will help solve quantum gravity or dark matter.

In the main I only see reason and balanced in this post, but this particular statement is a bit risky. Historically, big breakthroughs in the sciences happen when new measurement techniques become available or existing measurement techniques are refined to produce a "significantly" greater level of accuracy.

A breakthrough in our understanding of reality could come from anywhere that anyone pushes the bounds of what we can measure; which admittedly is probably the folk with the budget for a big particle accelerator, but one could imagine a path for almost anybody to make a contribution. One of the take-aways of the whole quantum vs classical business is that just because the evidence seems to be converging on a well respected model doesn't mean that the evidence is actually going to converge.

I definitely agree with you and mathgenius that mathematical techniques and technological progress created while investigating macroscopic behavior may be useful for making breakthroughs in "fundamental" physics. There is certainly precedent for that sort of thing. Perhaps complexity theory will have some significant impact on physics this century, who knows. But it's unclear whether there's anything that pure mathematics or mathematical analogies to the macro world can tell us about how gravity and quantum mechanics are unified, or any of the other big open questions at the bottom.

There is a large overlap of mathematical techniques between cond-mat and high energy physics. This has led some to speculate that particles are just excitations in some deeper "condensed matter" substrate.

Overall I find Hossenfelder's attitude to be far too negative. I'm fine with canning the big particle accelerators, but apart from that, there is a huge amount of exciting research going on in physics, theoretical physics (not just high energy stuff!), and mathematics.

> There's nothing wrong with studying condensed matter physics, and there is a huge amount to learn. But I don't see a conceivable way in which discoveries made by studying complex behavior closer to our scale will help solve quantum gravity or dark matter.

Interestingly, this does actually work out. Excitations in solids are often described by quantum field theory, and many of the exotic ideas of field theorists in fundamental physics turned out to be things you can actually find in a sufficiently exotic material.

She is not claiming that high energy physics is foundational. The foundations of physics are the main theories on top of which the whole edifice is built. In physics, these foundations include the Theory of Relativity and the Standard Model of Particle Physics.

We know that the foundations are incomplete because the Standard Model cannot be combined with General Relativity, although there is overwhelming empirical evidence in favor of both. They also fail to predict Dark Energy and Dark Matter. So we know that there is something foundational we don't know. One of the hopes of finding out what this is is to gather more empirical data (also allowing one to put many hypothesis to the test along the way). On the side of the Standard Model, high particle physics provides the theoretical and experimental framework to gather more such empirical data, that being the purpose of the particle accelerators. The author is lamenting that these efforts did not produce the results we were hoping for, and that they did not lead to any breakthrough on the foundational mysteries.

I do not quite agree with your foundations of Computer Science. For me, these are the theoretical constructs that give sense to everything else, for example Turing Machines and the main results on Turing Machines. Perhaps also Lambda Calculus, or at least combinatory logic and so on.

Another example: in modern Biology, the concept of "imperfect replicator" is foundational. If you remove that piece, the whole edifice crumbles into stamp collecting.

> in modern Biology, the concept of "imperfect replicator" is foundational

Can you share some references to this concept? Google Scholar with "imperfect replicator" doesn't help me much. Thank you.

It's just a very succinct and abstract description of the modern synthesis of Darwinism and genetic theory.

All organisms are self-replicating mechanisms, in the sense that they can generate a new organism that is built from the same DNA program (replicator) with mutations and possibly recombinations in the program (imperfect). The fact that the replications are imperfect is what allows for evolution to emerge. Together with survival-of-the-fittest mechanisms, this explains why life is so complex, why this complexity tends to increase with time, why there are so many species and so on.

It is possible to understand many details of nature by building on this idea. Higher-order theories if you like: why do organisms from different species sometimes look so similar? Why do certain organisms, such as the peacocks, have features that seem so unpractical, etc. Without it, we would be left with just cataloging stuff, as we once were.

>Together with survival-of-the-fittest

There are actually many more mechanism in evolution, such as genetic drift or geographic separation. You're merely focusing on one special aspect of evolution here.

Biology in practice is a quite messy science.

Fitting quote:

Another curious aspect of the theory of evolution is that everybody thinks he understand it. I mean philosophers, social scientists, and so on. While in fact very few people understand it, actually as it stands, even as it stood when Darwin expressed it, and even less as we now may be able to understand it in biology (Jacques Monod)

> There are actually many more mechanism in evolution, such as genetic drift or geographic separation. You're merely focusing on one special aspect of evolution here.

No, it's not some ad-hoc aspect among many. Notice that I was trying to illustrate what it means to say that some theory is foundational in a field. It means that, if you remove it, the rest of the edifice falls apart.

Imperfect self-replication and survival-of-the-fittest are foundational in that sense. You cannot make sense of concepts such as speciation through geographical separation, neutral mutations, theories about why genders exist, kin selection, eusociality, etc etc etc without those foundational pieces.

What you say is a bit like saying that the Theory of Relativity is just one special aspect of theoretical physics: there's also planetary dynamics, for example.

> Fitting quote:

The danger with these types of quotes is that they tend to end up applying to oneself.

Lee Smolin, who's a well-respected physicist, says similar things. He's especially critical of string theory, which lacks support from experimental evidence.

There is experimental progress in physics, but it seems to be at the low energy end. Down near absolute zero, where quantum mechanics dominates. Many of the stranger predictions of quantum mechanics have been confirmed experimentally. Useful applications, such as quantum cryptography, are emerging. That's where the action is.

Peter Woit is another theoretical physicist who says similar things.

Both Smolin's book 'The Trouble with Physics' and Woit's 'Not Even Wrong' are well worth a read.

If you like these books, then you might also like Unzicker book "Bankrupting physics". But be aware that there are very good arguments, that all these books are pure crackpottery: https://motls.blogspot.com/2013/07/shmoits-face-german-compe...

Lee Smolin is not a well-respected physicist.

"I don't believe that there exists a competent physicist who doesn't agree that Lee Smolin is a hardcore crackpot"


"When the whole world is running towards a cliff, he who is running in the opposite direction appears to have lost his mind." - C. S. Lewis

$20 billion spent is a lot of high tech jobs being made. I'm for it. Think how much we spend on wars.

Sure, but is this the best way to spend that money?

As Scott Aaronson put it[0]:

> I’m not making the much stronger claim that this is the best possible use of $20 billion for science. Plausibly a thousand $20-million projects could be found that would advance our understanding of reality by more than a new collider would. But it’s also important to realize that that’s not the question at stake here. When, for example, the US Congress cancelled the Superconducting Supercollider midway through construction—partly, it’s believed, on the basis of opposition from eminent physicists in other subfields, who argued that they could do equally important science for much cheaper—none of the SSC budget, as in 0% of it, ever did end up redirected to those other subfields. In practice, then, the question of “whether a new collider is worth it” is probably best considered in absolute terms, rather than relative to other science projects.

[0] https://www.scottaaronson.com/blog/?p=4122

Does it have to be the best?

Obviously not, but even many physicists are suggesting that the 20 billion could be spend better.

Given the alternatives it is likely to go to, pretty likely.

There’s definitely better things it could be spent on. It’s just that that will never happen. So we pick the best of the worse things.

You missed her linked tweet where she counters that exact argument.

Lots of high tech jobs come from war too. Great strides in physics came directly from war funding. Huge areas of tech (gps) came from the preparation for war.

Maybe it's me, but I would give more thought to her arguments if she wouldn't mention her book in /every/ post. She is really trying to sell it hard.

I think her tone is quite antagonising and I am not sure if it is intentional:

" No one wants to live in a world where the little German lady with her oh-so rational arguments ends up being right. Not even the German lady wants that. Wait, what did I say? I must be crazy."

This is meant to sound self-deprecating (I think) but in the context of the articles comes across as arrogant to me because clearly she thinks she is not the little lady, and others are irrationally ignoring her superior insights. Could be a cultural artefact but it makes her articles uncomfortable to read for me.

For what it's worth, I (British) think it sounds fine. It's the sort of thing I can imagine myself or a number of my friends saying. Very probably a cultural thing.

The section on Lisa Randall seemed unnecessarily personal as well.

She wrote that book because the problem really bothers her. It doesn't surprise that she's referring to it when discussing it, in my opinion.

Does it need a whole book to explain? It seems the current post does a fairly good job of getting the point across.

The book is lays out the full argument as opposed to a quick summary of the argument. It's moderately technical. I don't think it would make sense without a background in physics.

Compared to a software product, the scientists have build a product that contains many modules that all link together via complex maths. What is still missing is refactoring: making things simple again and removing unnecessary parts.

While many of the modules have been tested separately, certain combinations may not work as proclaimed. I find this problem already with the physics of the sun. So many things are way off normal physics. I have seen models that do not exist anywhere else. Predicted values are 10^6 order off. These things need retesting and the modules likely need to be redesigned.

But just stating that something might be off, already triggers many scientists. They see it as an attack on "their" science. This is clearly an attack on the messenger. Usually mixed with logical fallacies. So there is a real problem with the involved scientists as well. They do not want to see errors in their system, as it hurts their status. And there is the real problem with science. The ones involved do not want to admit that there might be something wrong.

If I would tell programmers that something might be wrong with one combination of modules, they are (more) often happy to look into it. So scientists, be more like programmers.

Would throwing 1000 particle scientists and 20B at fusion speed up it's progress?

I think the issue with fusion is similar to the arguments made by the lady in OP. Yes, fusion is under-funded but partly because people doubt that it's possible at all. OTOH, there are definitely people who have seriously good proposals for further fusion projects e.g. [1].

[1]: https://www.youtube.com/watch?v=KkpqA8yG9T4

I have never heard that people think fusion is impossible. It looks more like a flight to the moon appeared around 1960. You know it’s possible but there is a lot of engineering needed to make it happen.

The problem is it's not even known whether the engineering problems can be attacked at all, unlike the Apollo program where even though a large amount of work (Breadth rather than depth this time) it was an iterative evolution of past programs.

In 1960 they had no idea how rendezvous in space or a lot of other things would work but they knew they would figure it out with enough time and money . From whatever I have heard about fusion I have never heard about doubts about feasibility. It’s about trying out different things and getting experience since the knowledge in plasma physics is so thin.

We are doing it. Expected cost of cost of building ITER is now well in excess of 20B and keeps rising. It's not speeding anything up; first plasma not expected until 2025.

It’s got to be those bloody Sophons blocking progess!

Can you believe it, I opened this up and Ctrl+F'ed 'sophon' to see if I'd be the first one. Glad to see someone else beat me to it.

Ha, same

Try telling a homeless Veteran that it was worth $20 billion to prove the Higgs mechanism. We could house 400,000 homeless for that price.

Or why don't we do both. It isn't either/or. Taxes can be raised, especially on the ultra-wealthier.

If you're talking about the income tax idea by AOC it'll only boost taxes by 0.3%, assuming no tax dodging:


Well but how about a cutting edge silicon fab that gave the entire world a powerful device that fits in one's pocket to access all of human knowledge, instantaneously? For 20B? Add to this the fact that technology is powered by science and you get a very different picture.

Why is it I generally only ever hear this argument (or some variant of it, e.g. starving children) when discussing a proposed scientific endeavour? Why not trim the US military budget by 10% and generate 3x as much revenue, you could house 1.2 million homeless for that price.

With $20 billion, you could house 400,000 homeless people for three or four years, not forever. And that's assuming they need only rent and not mental health or other services.

Wild idea:

Either there is a loophole in physics or there is not. By 'loophole' I mean 'some of the physics we don't yet know, has useful applications such as faster than light travel or unbounded computation, that could potentially be tapped by terrestrial civilization'. (As opposed to the alternative state of affairs where the Standard Model suffices to describe everything that will ever happen in our solar system.)

The expected value of research in fundamental physics is much greater if there is a loophole than if there is not.

Proposal: we should try to figure out what qualities the as yet unknown physics must have, conditional on a loophole existing. Then we should proceed on the assumption that it does indeed have those qualities, in order to maximize expected utility.

Interesting idea, though I would say if it’s measurable then we can’t rule out an application somewhere down the line no matter how esoteric the knowledge might seem now.

Rule out absolutely, no, but we can say some kinds of physics are much more likely to be applicable than others. And what matters is applicability by terrestrial civilization. 'This could be applicable, but only by a civilization capable of building Dyson spheres' is irrelevant to us, because if we get to that point, we will already have made it past the Great Filter.

Sabine Hossenfelder has received an incredible amount of shit that she absolutely doesn't deserve, including in this comment thread.

What she's talking about is all stuff that's well known in the physics community. She is willing to say it publicly.

I don't really understand what she's suggesting. It is easy to be sceptic, and just saying that "ya'll just wasting money". And to be honest 20b on a collider is a tiny dent on budgets we spend on, say, military.

How many particle physicists are we throwing at this problem?

I heard that to get interesting data we are actually supposed to throw them very fast against each other.

In general, it would be quite interesting to see how many scientists, technologists and mathematicians are working on which problems. For the latter group, I've seen estimates that there are less than 350,000 researchers worldwide.

Is there any chance that we could reach new physics with a linear collider instead of a circular collider?

If there is, then I have an idea to get funding. Build it above ground along the US/Mexican border, so that it could also serve as the wall President Trump wants built.

I didn't read every comment, I skimmed as many as I could. A question: how much of the hate/distain/put-down/vituperation is because she's a she and not a he?

Seriously. I read at least three comments suggesting arcs of her argument are held by physicists with the requirements between the legs. Is it just how she says it, or is it because she has a vulva?

this is a core part of the plot to https://en.wikipedia.org/wiki/The_Three-Body_Problem_(novel) -- a fantastic read which introduced me to a lot of Chinese perspective and history i never received elsewhere.

She says:

> But the problems that theoretical particle physicists currently try to solve do not require solutions. The lack of unification, the absence of naturalness, the seeming arbitrariness of the constants of nature: these are aesthetic problems.

What are some examples of problems that do "require solutions"?

From physics, it seems like cosmology has a whole bunch. What the heck is dark matter made out of? Why is the the expansion of the universe accelerating? These seem qualitatively different than the "aesthetic problems" she points to.

She's painting with a broad brush. Neutrino mass is a problem that does require a solution, but as far as I know, a lot of theoretical particle physicists are trying to find solutions to that problem.

The nature of dark matter, for one. Gravity at quantum dimensions...

I feel like there is probably some new physics out there, maybe entropic gravity or something, since there are still some big mysteries out there. (Dark energy etc)

That said, I would be very surprised if we discovered anything with as much practical use as say, quantum physics or electricity or thermodynamics.

> That said, I would be very surprised if we discovered anything with as much practical use as say, quantum physics or electricity or thermodynamics.

History keeps proving that we will.

I mean hey, maybe I’m wrong but I have a bachelors in physics and this is what I’m seeing ahead. Verifying the speed of light is easy; you just need a rotating mirror and a laser or bright light. Showing that electrons have a charge can be done with oil drops. But the Higgs boson took, let’s just say a bit more effort, and while I think it’s good that we are looking for new particles there is no practical application of the Higgs. Just saying. The low hanging fruit is gone and what’s left may or may not be useful.

Well one solution would be to start aggressively funding the LHC's successor, since in lieu of some better places to go looking for new behaviors we're going to need a higher energy particle accelerator if nothing comes up.

"...the greatest physicists such as Einstein, Dirac of Schrödinger would have considered the “discovery” of the Higgs particle ridiculous."


But who will be making the decision to build the next accelerator?

The article is far from constructive criticism. In the end is blaming the general current approach but it does not offer any alternative solution. It's easy to say 'you are not doing it right' unless you can do it right.

Quantized space and Quantized inertia both have interesting potential and both involve reframing existing ideas.

What has dark matter anything to do with the standard model? Dark matter is just a hack for Einstein relativity theory.

Dark matter is a stuff that exists, we’re pretty sure, and some explanations for what it is would involve expansions for the standard model; seeing if one of those explanations is right is therefore a (supposedly) promising avenue for post-standard model physics.

Maybe one should read more before downgrading other people’ comment as nonsense. Excerpts from Wikipedia (text in square brackets are my): Dark matter is a hypothetical form of matter that is thought to account for approximately 85% of the matter in the universe...[speaks the existence of dark matter existence is not proven, is not even part of the standard model!]


Its presence is implied in a variety of astrophysical observations, including gravitational effects that cannot be explained unless more matter is present than can be seen.


The primary evidence for dark matter is that calculations show that many galaxies would fly apart instead of rotating, or would not have formed or move as they do, if they did not contain a large amount of unseen matter.[2] Other lines of evidence include observations in gravitational lensing,[3] from the cosmic microwave background, from astronomical observations of the observable universe's current structure, from the formation and evolution of galaxies, from mass location during galactic collisions,[4] and from the motion of galaxies within galaxy clusters. [so mismatch in gravitational effect with Einstein General Relativity is the only reason why people think there “must” be dark matter out there. Imagining dark matter would help to keep Einstein General Relativity correct in its current form, in other words it’s a HACK!]


Although the existence of dark matter is generally accepted by the scientific community, some astrophysicists, intrigued by certain observations that do not fit the dark matter theory, argue for various modifications of the standard laws of general relativity, such as modified Newtonian dynamics, tensor–vector–scalar gravity, or entropic gravity. These models attempt to account for all observations without invoking supplemental non-baryonic matter. [means without the need for the hypothetical, non-observable dark matter. And because the standard model can not explain gravity, dark matter or modified gravity theory has nothing to do with the standard model as stated in my original comment]

For what it's worth, I didn't downvote you- but you should realize the gap between what your Wikipedia source says and what you originally asserted. Yes, Wikipedia is right that the existence of dark matter isn't proven, and it's also true that there's no proven connection to the Standard Model; it's also true, as I said, that scientists are pretty sure that it does exist (the alternate theories are widely regarded as long shots.) And if it exists, this novel form of matter would need to be fit into the Standard Model somewhere, since that is intended to describe all forms of matter.

Incidentally, I also think you're getting your history of science confused; the "cosmological constant" term Einstein used to make relativity consistent with his belief in a static, non-expanding universe was a "hack" (he himself wound up admitting it was unjustified.) But that's entirely unrelated to dark matter. Similar modern theories to the cosmological constant have been termed "dark energy," but the use of the word "dark" in both doesn't imply a real connection- it simply means that they each haven't been directly observed.

This person writes like cranks write: self-aggrandizing for the most part. I don’t know enough about HEP that I’m going to just treat it as a crank text.

Maybe my (ex) university was right to close down its Physics Department decades ago, after all. They timed it well, soon after all those predictions started going all wrong. The decision was taken by accountants and at that time I never thought that they were that clever but maybe the market forces understand it better than we do?

That blog keeps rambling on about the same old thing over and over. Maybe the author is crazy. What is being proposed here, to abandon all physics research because it has become hard? And in the end constant nagging is not fruitful to anything, unless the author can reasonably argue for a new line of research.

As an aside, Physics is not even suffering from true scientific issues such as reproducibility and direction of research.

>That blog keeps rambling on about the same old thing over and over. Maybe the author is crazy. What is being proposed here, to abandon all physics research because it has become hard? And in the end constant nagging is not fruitful to anything, unless the author can reasonably argue for a new line of research.

she did just that in the NYT piece that is also linked to in the blog post.

"And there are other avenues to pursue. For example, the astrophysical observations pointing toward dark matter should be explored further; better understanding those observations would help us make more reliable predictions about whether a larger collider can produce the dark matter particle — if it even is a particle.

There are also medium-scale experiments that tend to fall off the table because giant projects eat up money. One important medium-scale project is the interface between the quantum realm and gravity, which is now accessible to experimental testing. Another place where discoveries could be waiting is in the foundations of quantum mechanics. These could have major technological impacts."

There really is no argument in favour of why building a new, extremely expensive accelerator is reasonable. We don't expect to find anything at those energy levels, it is pure guesswork.

i believe astronomy is not underfunded, with projects like JWT. now she might be right about medium scale projects but one would have to see the budget for it. Research directions is a difficult matter, and as evidenced by recently identified problems with medicine and biology reserach, having a ton of medium-sized projects instead of a few megaprojects is not necessarily more fruitful.

No no: she rambles about (mostly) supersymmetry and related “physics”-without-refutability. She does care about science: she is tired of theories without real (as in “real world”) support.

The only scientific pursuit worth pursuing is the transfer of the human mind to a machine host. Once that is done, we'll have forever to do everything else, including interstellar travel.

Imho we need to be facing up to the implications of quantum mechanics. All of this brain power going into particle physics should be going into the most baffling and fundamental discovery ever made. We need to experiment the f* out of the phenomena and take seriously the implications.

You might like Greenstein and Zajonc's book 'The Quantum Challenge' is talks about a lot of the research in the foundations of quantum mechanics, which is a thriving field in its own right. It's also incredibly subtle and basically impossible to sell popular books with. The book I mentioned is most emphatically not a popular science book.

> the most baffling and fundamental discovery ever made

...Which is?

A baguette

Physicists don't have any imagination to break past certain assumptions (e.g wave function collapse is random)

I liked Stephen Wolframs ideas around cellular automata and network based structures -- it seems that if we could look at physics as more of an information transfer problem -- paired with network optimization and information storage optimization, on a network: this is where real progress will be made. There have been theories around emergent spacetime from thermodynamic processes that were abandoned and IMO need to be re-investigated.

I highly doubt that wave function collapse is just completely random. We just don't see the structure that is creating the "random" distributions we observe.

This is far from a new idea, and is called the "hidden-variable theory" [1]. In fact, it has been mathematically proven that locality and hidden variables are fundamentally incompatible in the context of quantum mechanics.

[1] https://en.wikipedia.org/wiki/Hidden-variable_theory

Wolframs idea [1] is that space is a network, and closeness of points is determined by the links in the network. A particle is an extra structure that is connected to some of the nodes in the network, so if two particles are connected to nodes far way in the network, but also have several links between each other, they won't have enough links to change the structure of the space, but will be connected enough to affect each other in the Bell test.

I'd say this resolves the hidden variable and locality conflict beautifully, by changing the concept of locality to something much simpler than the infinite continuum. And it is also somewhat similar to ER=EPR [2] hypothesis Susskind talks about. But unfortunately it is only a vague idea so far.

[1] https://blog.stephenwolfram.com/2015/12/what-is-spacetime-re...

[2] https://www.youtube.com/watch?v=pY5D7ZgWuXc

Maybe it's nonlocal then.

> I highly doubt that wave function collapse is just completely random. We just don't see the structure that is creating the "random" distributions we observe.

What you're talking about is some form of hidden variables theory[1]. This has been the topic of significant research since the days when Einstein and Bohr had their great debates before WW2. We've had sufficient development in both theory and experiments on this topic to say that either

i) there is "just" standard quantum mechanics

ii) you must abandon local realism, i.e. it is impossible to do independent separated measurements of a quantum system

iii) the world obeys superdeterminism, i.e. there is no free will

[1] https://en.wikipedia.org/wiki/Hidden-variable_theory

Have you seen the blog post at question https://blog.stephenwolfram.com/2015/12/what-is-spacetime-re...? It proposes the 4th way, that is the space is a graph, that only approximately maps to the 3d continuum, so non locality is introduced only as an artifact of mapping, and everything is local on the graph.

> iii) the world obeys superdeterminism, i.e. there is no free will

Superdeterminism doesn't simply say that there is no free will. (Normal determinism says that too!). The problem with superdeterminism is that it requires the hidden variables to work in a very complicated way.

If Alice asks her friend to play mario and give her sequence of 1s and 0s for winning and losing, and Bobs friend plays golf, superdeterminism requires the outcomes of this games to be exactly correlated with the experiment with photons Alice and Bob will do next year!

> Physicists don't have any imagination to break past certain assumptions (e.g wave function collapse is random)

This is not quite fair, after all Wolfram himself have worked as a physicist.

What physicists do not do, is they do not usually talk much about ideas for which they had not found any mathematical model or any analogy with existing theories.

Wolframs idea is very enticing, especially if you like the idea of digital physics and want to get rid of real numbers in the theory. But unfortunately it is very hard to get some working mathematical model from it.

Well, since you have that imagination, I'm sure you'll produce a workable theory any day now...

How does your model make quantitative predictions?

All evidence suggests that quantum mechanics is probabilistic.

Can you explain more and share references?

The simplest and most popular interpretation - the Everett interpretation - is the most popular with physicists, and wave function collapse is a completely non-random process in that theory (and isn't even really a separate process, but rather just what happens when you apply thermodynamics to wavefunction evolution).

> - the Everett interpretation - is the most popular with physicists

Source? On the contrary, this survey of physicists https://arxiv.org/pdf/1612.00676.pdf (Fig 13.) indicates Copenhagen is dominant, followed by no preference, with Everett a long way behind. This is also matches my perception as a former member of the community.

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