>Despite the silly clickbait title of this video, Sabine says a lot of interesting stuff in it: her criticism of claimed deviations from Lorentz invariance in loop quantum gravity is about as good as you'll get from anyone who hasn't actually worked on loop quantum gravity. I worked on it for about 10 years, and the situation is even a bit worse than she makes it sound.
I know people have strong reactions to her and her sensational style, but that is a serious recommendation from a knowledgeable person, so I think we can give this thread a second chance. (Someone emailed and asked us to.)
All: please let's keep the comments on topic and substantive (and avoid the sensationalism and personality aspects).
30 years ago I spoke to a fairly well known and regarded physicist who said something rather interesting along the same lines. Quoting as accurately as I can "physics looks sexy from the outside due to some celebrities but inside it's mostly worse than anyone wants to admit.". He also suggested I go and study mathematics instead because at least there will likely be some applications for it. I did and I am glad I did.
Sounds like this criticism would be valid for fundamental physics but there are many other physics fields with experimental results that become technology.
IANAP but it seems that fundamental physics suffers from a lack of monotonicity of knowledge. Although physics does its best to explain things, those explanations are more like guesses than known facts. A theoretical physicist can have their life's work undone simply because someone else comes up with a better guess, or experiment says no. You spend your life working on SUSY and then... nope. Even very established knowledge can be overturned.
People will say "that's science" and indeed that's fundamental physics, but other fields don't really work like that.
In chemistry and biology, certainty isn't in such short supply. Nobody is asking "but is DNA a double helix?" Researchers take a problem, they attack it, then they publish the results, it gets replicated (or not), and the set of knowledge grows.
Mathematics is more similar to chemistry and biology insofar as mathematical knowledge takes the form of an ever-growing set of proven facts generated by research. Take a problem, prove it, other mathematicians check it, the set of knowledge grows.
Fundamental physics has issues because the "check" stage now often costs millions or billions of dollars (build a particle accelerator, neutrino detector, gravitational wave detector, satellite, etc), and even then it might not give a definitive answer. Just look at the g-2 situation where they notice a discrepancy, they spend millions of dollars trying to determine if this single discrepancy is real, and then someone publishes a paper "haha I recalculated it, you just wasted your time".
Not a criticism of fundamental physics because clearly that's just how it is. I'd rather have guesses than ignorance. The gravitational wave research seems to be doing okay at least.
> John Carlos Baez (/ˈbaɪ.ɛz/;[2] born June 12, 1961) is an American mathematical physicist and a professor of mathematics at the University of California, Riverside (UCR)[3] in Riverside, California. He has worked on spin foams in loop quantum gravity, applications of higher categories to physics, and applied category theory. Additionally, Baez is known on the World Wide Web as the author of the crackpot index.
He was also a long-time maintainer of the Usenet Physics FAQ and has been writing about physics and mathematics on the internet for decades. So not only is he the real deal in terms of knowledge, he also has a long history of communicating that knowledge to the public, albeit typically for a more advanced audience.
I'm not hot on what fundamental physics looks like now or in the future, but there's an attitude that Sabine promotes that I see echoed in a lot of comments here which feeds into problems with research.
I don't think the work put into studying fundamentals was "a waste of time" thus far. It's dangerous to label experiments and ideas that were acted on in good faith as the best options at the time but didn't yield positive results as missteps.
Scientists need to be allowed to do work like this without fear because to do so otherwise leads to perverse incentives and you end up with things like lots of studies that can't be reproduced because of p-hacking or worse.
Arguing bad faith after the fact is awfully hard without real evidence and if you're going to discount anyone with enthusiasm for their research proposal based on enthusiasm alone you're not going to be left with a healthy program. I don't blame anyone who supported things like supersymmetry as an example for something which hasn't panned out. we're still left with a major mystery and big questions and it says we need to rethink things in more difficult directions.
The whole of human society is a combustion engine for life, barely held from going full self destruction by a science driven economy consuming resources in a unsustainable way. Science is what kept us peaceful and nice since WW2. And the breakthroughs are needed not some time far far away ,they are needed now. This is not about the purity of approach or some hypocritical game. This is a dependancy of life and death on the results ..
I'm not in any way an expert in this area, but here is what I see. I don't think the argument is that it's being said as "bad faith after the fact". I think the argument is that the approach was told it had fundamental flaws. Those were ignored / denied. People continued to invest in it and suck up all of the research and bright minds in the field. Decades later it still has those fundamental flaws and has taken over all other possible avenues of progress as it has all grant money and and the majority of all departments working on it.
It's more "you were told this is broken before. It's decades later and it's broken in the same way. At what point to you admit that this approach isn't working so try something else?" And the answer is "No, we're going to keep digging deeper".
Fundamentally, approaches need to be falsifiable. If your theory is "falsifiable" in the small scale but ultimately unfalsifiable in the large scale then it's is fundamentally unfalsifiable and we can't use it to lead experimentation.
It's a breadth vs depth search question. We've lost all breadth of search in physics, because a little ways back we stumbled upon a branch that happened to have a (for practical purposes) infinite number of subbranches relating to ways to roll up string dimensions. So physics is stuck exploring all of those sub-branches instead of backtracking one level and exploring any other parts of the tree.
The argument is that everyone is looking under the lamppost for the keys. After 4 decades of searching there, maybe it's time to search somewhere else. And the argument is made even strong when decades back they were told, "Hey, I didn't drop by keys by the lamppost. I dropped them somewhere else". And yet most people keep looking there.
Sabine's argument has been frequently bad faith after the fact and currently. Just skimming some of her written work:
"Before the Large Hadron Collider turned on, particle physicists claimed that it would either confirm or rule out supersymmetry. ... The answer is that the LHC indeed did not rule out supersymmetry, it never could."
When people are accused of ignoring or dismissing credible points where a program is legitimately problematic is exactly an accusation of operating "bad faith". "Good faith" means doing legitimate and believable science with the best information. These are claims it was done to the contrary.
My understanding of the situation (which may be wrong, in which case please let me know) is that physics is stuck at a local optimum.
There are two obvious ways to get out
(1) Surprising physical observations, or
(2) Mathematical advances
Way (1) is what kicked off quantum mechanics. Way (2) is what kicked off Newtonian mechanics.
I see string theorists and loop quantum gravity people as working on (2). Their models are mathematically interesting and aren't totally understood from a mathematical perspective. But they're different enough that studying them may break the impasse.
I see (1) as largely limited by the budgets and technology needed to build things like particle accelerators and spacecraft.
For (2) you have to decide whether to only explore mathematics that defines physical reality, or whether to also allow exploration of non-physical systems. For example, you might explore a universe that is almost physical but has time machines. Restricting the search space to only physically realistic systems is a significant constraint, so there's a debate to be be had about how much weight to give it.
I think I heard somewhere that the trouble with string theory is it can describe anything if you tune it just in a right way. It reminds me of epicycles, they also had this property, you can add more and more epicycles to describe literally any observation data.
> Way (1) is what kicked off quantum mechanics. Way (2) is what kicked off Newtonian mechanics.
Hmm... What was the way that kicked Copernicus to redraw epicycles with the Sun in the center? I mean, is there some notes on these? For example, Newton took as granted that celestial bodies move by elliptical orbits, and somehow he guessed that the gravitation law has r^2 in its denominator, and so he invented calculus to prove, that if you have r^2 in the denominator then you'll get elliptical orbits. The question where Newton got his guess it remains open for me, but back to Copernicus, what was his way?
Maybe he thought how movements of planets will look if seen from the Sun, and so he had redrawn epicycles to take a look, and he got circles? (I'm not sure that it could work this way, I propose this answer to my question just to give an example of the kind of an answer I'd like to have).
I ask this question for two reasons.
1. I believe that Copernicus advanced the science not with surpising physical observation and not with mathematical advances, to me it seems more like surprising mathematical observation. I'm not sure what was that observation exactly.
2. Can one apply techniques of Copernicus to the modern physics? I suspect that it will not. I'm sure physicist already tried everything and there were (is) a lot of them and they are pretty smart people, so it is highly unlikely that Copernicus can help them in any way. But I'm still curious, what Copernicus would do? Would he tried to imagine how electron flying through a double-slit might observe scientists-observers? Or maybe it would try to feel the pain of a black that may believe that the whole universe is falling on it? I bet that the true Copernicus idea would require to use some pretty hard mind-altering substances, and I like such ideas.
Copernicus used the same circular-orbit-plus-epicycles system as Ptolemy, just the orbits were centered around the sun (kind of---each planet had its own circle, with the sun only approximately in the middle). The system actually had more epicycles than Ptolemy's and was less accurate. It wasn't an advance in any meaningful sense.
The real breakthrough was Kepler, who dropped the idea that planets moved in circles. It was indeed partly a mathematical breakthrough and the reason Kepler's work took a while to catch on is that people couldn't understand his math at first. But it was also empirical, as Kepler had access to new and much more precise observational data collected by his mentor Tycho Brahe.
1. Copernicus figured out that if you put the sun at the center, then epicycles weren't necessary, and the math got easier --- because epicycles were based on a mis-understanding of the actual state of the universe --- I don't believe that anyone has identified such a non-alignment of fact and reasoning and observation for contemporary physics.
2. The problem is, modern physics is arguably getting boxed into a corner by approaching an end game state where the fundamental particles are getting identified, but are so small and difficult to separate out, that measurements are challenging to the point that while one can speculate and do math, actually proving out the speculations experimentally and taking actual measurements is expensive or so difficult to reason about that there doesn't seem an obvious path to an experiment, e.g., it looks as if the electron may be a fundamental particle, which is a sufficiently difficult concept to parse that it led to "The one-electron universe"/"The single electron hypothesis" and if that is the case, it walls off a not insignificant portion of particle physics at a size/state which can't be gotten smaller than.
I can probably answer the r^2 question: it’s the scaling associated with the surface area of a sphere. So if you have light source, or a sound source, that’s how it scales with distance. It would have been relatively simple for someone as smart as Newton to guess that gravity worked the same way.
It’s only really our current understanding of gravity that makes it unobvious.
Everett proposed that observation happens relative to observer, it's exactly Copernicus's observation. Some people buy it, many don't, so I guess heliocentric style thinking is still counterintuitive. Ironically, an argument against Everett's interpretation is the same Aristotle used against heliocentrism: "it's not supported by observation" (meaning relativity is unobservable).
Those mathematical advances weren't developed in a vacuum, but made to solve some very specific problems which came from better measurements. So even Newtonian mechanics originated in solving problems trying to explain measurements, not that someone sat in their chamber and dreamed up cool math that happened to be very useful.
Number theory and algebraic geometry were developed for their own sake (i.e. "it is cool"), but later people found practical applications in cryptography.
So "useful math must be motivated by practice" is empirically false
Name a single physics phenomenon that was discovered purely with way 2. I can only think of one, the positron.
Newtonian physics was not kicked off by math "advances". Approximately speaking it was the other way, Newton created the math to explain p^2 ~ r^3, which was a surprising observation.
Even theory of relativity wasn't really a math advance, the math was already mostly worked out by mach, lorenz, and minkowski. Einstein put it together into a coherent story (v. Important)
Bose-Einstein statistics, which originated purely from finding a derivation of an equation, without immediately understanding of the true physical meaning of the derivation.
And then Bose-Einstein condensates; a thought-experiment consequence of Bose-Einstein statistics.
Radio waves etc., from formulating Maxwell's equations.
This might be too weird to be true, but when I heard that Geoff Hinton got the Nobel prize for Physics, I wondered if the prize committee was having trouble finding "real" physicists who had made fundamental advances....
This is not meant to knock Prof Hinton. These are his own words:
“I’m not a physicist, I have very high respect for physics,” Hinton said. “I dropped out of physics after my first year at university because I couldn’t do the complicated math. So, getting an award in physics was very surprising to me. I’m very pleased that the Nobel committee recognised that there’s been huge progress in the area of artificial neural networks.”
It is evident that they need more than five categories. Awarding Nobels to individuals who are not particularly (if at all) well-versed in the subject at hand, even if they contributed to a breakthrough in the field, directly or indirectly discredits the prize.
Indeed, the online memes about Hinton and Hassabis being "a bit of a <physicist|chemist> myself!" are justified, in my opinion.
I agree with you. What is also telling is that there is no particularly strong reaction from the physics community that someone obvious was wrongfully omitted.
> What is also telling is that there is no particularly strong reaction from the physics community that someone obvious was wrongfully omitted.
A few days before the announcement of the Physics Nobel Prize Sabine Hossenfelder created a video about her predictions for the Physics Nobel Prize. Likely all mentioned researchers in this video did more for the advancement of physics research than John Hopfield and Geoffrey Hinton:
> Who Will Win This Year’s Nobel Prize in Physics? My Speculations
If LQG turns out to be unworkable, we're back at string theory as the only renomalizable description of quantum gravity.
Quantum gravity research amounts to one professor per university faculty on average. Even in the worst case this would not be the crisis of unmet expectations it is made out to be... QG researchers are very brave because they are risking everything on the possibility that existing data constrains quantum gravity in a way that hasn't yet been understood. I doubt there is even a single person making that gamble unaware that the Planck energy density is something like 20 orders of magnitude above present-day experiments.
> we're back at string theory as the only renomalizable description of quantum gravity.
I think you mean, we're back at "we're not sure if string theory is a viable theory of anything real".
Quantized gravity is not necessarily the right answer, and an insistence on this fundamental assumption might be the origin of these difficulties, eg. see Oppenheim's semi-classical gravity.
The fundamental reason for this is simple. Humans are prone to cognitive dissonance. Meaning, we do absurd things to avoid painful thoughts. And anything that questions our sense of identity, is a painful thought.
So if my self-image is, "I've advanced our understanding of the fundamental nature of reality," then the idea that my contributions weren't useful becomes painful. So we avoid thinking it, challenge people who question our past contributions, and so on.
The natural result of this cognitive dissonance is a feeling of undue certainty in our speculations. After all certainty is merely a belief that one idea is easy to believe and its opposites are hard to believe. We imagine that our certitudes are based on fact. But they more easily arise from cognitive biases.
And this is how a group of intelligent and usually rational people descend into theology whose internal contradictions can't be acknowledged.
And reinforces my general below-the-line (layperson) fear about the state of physics today (as reinforced ofc by the likes of Sabine Hossenfelder & Eric Weinstein).
I've been working on how to formulate that idea clearly for a while. It is a problem that goes well beyond physics. For example I believe that the same cognitive error is behind the fact that experts do significantly worse than chance in actually predicting the world, and the more certain the expert sounds, the less likely they are to be right. See https://www.amazon.com/Expert-Political-Judgment-Good-Know/d... for data demonstrating that fact.
Depressingly, this means that we consistently put public policy in the hands of people who are demonstrably incompetent.
To extend this, group dynamics can come into play too.
I once worked at a startup that developed fancy new tec. The group dynamic there was that critical thinking absolutely did not exist. The reason was probably that they accepted only people in their circle, that had the same burning positive attitude towards the idea.
This can become a self reinforcing circle, because critically thinking people will leave at some point. (Like sabine did in physics).
> So if my self-image is, "I've advanced our understanding of the fundamental nature of reality," then the idea that my contributions weren't useful becomes painful.
Only if one believes the logical fallacy that the dependent steps of a process of elimination weren't useful.
Even if you believe that they are useful, you're also not going to wind up as a hero in the history books. And so people wind up acting in the same way.
Besides, the argument that all of the bad ideas contributed to discovering the right one, is as strong as the empirical argument that white chairs are evidence that all ravens are black. Logically you're right. Discovering the right idea requires disproving all of the wrong ones. Similarly "all ravens are black" is logically the same as its contrapositive, "all non-black things are not ravens". It's just that you've just decided to focus on a search space that is so much bigger, that each data point in it becomes much less important.
Eh, in many ways the problem is a sunk cost fallacy type issue.
If someone is later in their career and looking at having to throw away all that time - time they will never recover - it takes someone really special to just do it.
And by really special I mean ‘kinda suicidal sometimes’.
This is where climate skepticism comes from by the way. Even climate skeptics will acknowledge that climate scientists are well educated, they don’t deny science as a process of truth seeking, the problem lies in the incentives.
There’s a lot of prestige and grant money that comes with insisting climate change is true.
There’s a lot of political power that gets ceded to the people in charge if we “just accept that we’re in a crisis and us elite are the only ones that can stop it”.
I believe climate change is real and human caused, but many of the claims and doomsday speak feel like self interested humans following their incentives beyond the scientific truth
What are you talking about? I spent years munging climate datasets from various research institutes around the world. The upshot: it doesn't look good for humanity. I seriously don't understand how a neutral third party can walk away from this climate work and think, 'Nothing to see here folks.' The denialism and willful ignorance of the potential catastrophic consequences is something I find terribly disheartening. Mark my words - the temperature records that keep getting broken year after year are going to keep getting broken. Entire towns going up in flames and cities being wrecked by increasingly more powerful hurricanes will be the new normal. <sigh>
You know how some people seem knowledgeable until they talk about your field? Well for me (molecular biology and genomics) this never happens with Sabine.
So, even though much of this is over my head, I grant her much credence.
I think the problem is more fundamental. Newtonian mechanics is a science based on observation. Mathematics is just used to build a model that describes _how_ the reality behaves, not why.
Now Einstein is very special, because he proved that our human perception of space and time is wrong. When we think about the allegory of the cave, we got a glimpse of the reality we couldnt see before.
Nowadays every phyiscist wants to be the next einstein that uses mathematics to show us something about reality. The problem is that einstein had good reasons for his ideas. The constant speed of light didn't really work with maxwells equations. The model at that time didn't correctly describe the observations and the maths he used to solve that is rather elegant and simple.
Her choice of background for this video and the matching imprint on her blouse gives us maybe a hint that "fundamental" physics is too broad a field to actually die :-) I.e., there are ongoing and deep puzzles e.g., in dark matter / dark energy where observational data keep accumulating and at some point a critical mass (pun) of evidence may reshape our ideas about how the universe fundamentally works. The new ideas need have nothing in common with pre-existing mind sets of how things work.
Now about the string theory / quantum gravity furore, after decades of work by arguably extremely bright people its pretty clear that Nature in the current juncture is not giving us enough clues to proceed. This should not be stressful - Nature is not a Hollywood production studio that needs to churn gee-wow "experiences" every season. But Sayre's law applies rather well [1] "In any dispute the intensity of feeling is inversely proportional to the value of the issues at stake.". What is at stake here is the ego of a few individuals that assumed otherwise (i.e., that a post-Einstein revolution is imminent) and the (relatively minor in the scheme of things) research funding of this particular niche of physics.
Theoretical physics is not the only domain bouncing regularly between "hypes" and "winters", as the recent Nobel prize for Physics clearly demonstrates.
I know that this will probably be down-voted to death but I don't like these hyperbolic takes. I know that Sabine did use this title for click-bate purposes that she is now mostly doing YouTube videos (she had horrible experience that unfortunately not rare in scientific community [1]). I understand that the field of particle physics which is the corner stone in fundamental physics is not showing the great advances that it used to have a couple of decades ago. But I think people really don't understand that the field is still advancing and although these advances are less catchy to be reported in mainstream (and don't get traction if posted on HN) it is not dead or dying.
There is a reason why we had a particle data group updating the PDG [2] each two years (you can order physical copies for free but please don't do if you don't need one). People were writing about that since after the big discovery of Higgs boson (that was 12 years ago). We still have a lot of measurement and puzzles that is less about unification theory that people usually would talk about. Theory people are coming up with all different ideas even if some are not testable now but that job of theorist is mainly come up with ideas and help bridge the gap later.
I would suggest everyone interested in this topic to read the electroweak current chapter of the book called "How experiments End" [3] to understand a historical example to how we approached the standard model when it was first proposed. Most of the particle physicists will not work on supersymmetry, string theory and these catchy theories that people will hear about. Most of the work is advancing and answering (and raise questions) piece by piece. Here is an example of interesting results that help us answer some questions [4]. Also I'm not saying that the field had its own problems and can improve on many aspects. I'm just against these extreme and hot takes that claims it is in a crisis or dying.
for people who posted the comment from John Carlos, I like this toot/tweet/comment by Sven Geier [5] which was what John replied.
Disclaimer: I'm a particle physicist and have a skin in the game.
Seems like you are not downvoted on HN for rational argumentation.
I still think sabine has a point. When we consider occam's razor string theory is absurd. Just because einstein used math to show our perception of the world is flawed, doesn't mean it is likely repeatable with an overly complicated mathematical model.
Yet we live in a world, where highly decorated physicists spin a tale of consciousness beeing enabled by the collapse of the wave function (and other absurd stuff like many world interpretation).
This wasted also my time, because it confused me for a while.
Let religion for the religious, philosophy to the philosopher. Physics should be a science based on observation.
My point was that sabine is claiming that the field is dying (or in a crisis). You can argue against string theory and quantum gravity research as much as you want. But this will not warrant sabine's conclusions about particle physics and why we should invest in other areas instead. She is doing this for almost a decade now.
And I don't understand your point about statistical interpretation and how it is related to being a religion. Pick up any of the mainstream interpretation and start doing calculations of lets say ground state energy of H atom and you will get the same results.
All mainstream interpretations yields the same results if calculations are done "correctly". The shut up and calculate works pretty well across interpretation because of two things you have to consider
The first thing is that all interpretations rely on four things to be able to do the calculations. ( I simplified a little bit)
1- Hilbert spaces to represent quantum states
2- Operators for observables (like momentum and energy)
3- Unitary evolution of states through the Schrödinger equation
4- Born’s rule for calculating probabilities of measurement outcomes
Thus, the underlying equations are the same regardless of interpretation.
The second thing you have to understand the role of Interpretations. They aim to explain what the mathematical structure of QM means. They differ on issues like: collapse, Is it real (Copenhagen)? just an apparent phenomenon (Many-Worlds)? or governed by additional variables (Bohmian mechanics) or the question of Determinism. Is the universe fundamentally deterministic (Bohmian mechanics)? or indeterministic (Copenhagen)?
The last thing is a really philosophical question about what exists physically—wavefunctions, particles, or multiple worlds?
These philosophical questions don’t affect the numerical predictions of quantum theory and that's part of the reason you shouldn't learn physics from science communication books.
Sabine is often right, but I think she's wrong here about Lorentz invariance being a problem, or at least a problem in the way she's saying.
Lorentz transformations are never going to length-contract the underlying fabric of space/spacetime. Relativistic length contractions contract moving objects, not the underlying spacetime.
In fact it's a strange and basic misunderstanding to have.
Sabine is correct. All objects in a spacetime are anchored to that spacetime, so if spacetime has a minimum length, then length contraction of moving objects has a detectable lower limit, thus violating Lorentz invariance.
She seems to be talking about spacetime itself being Lorentz contracted though.
it's true that a sufficiently fast moving object would be length contracted so much that it started interacting with the minimal LQG length, which would violate Lorentz invariance. Depending on how big the LQG loops are, that could be a fanstastically high speed that isn't achievable in the universe though.
Depending on your reference coordinate system, space is transformed. That is the entire point of relativity theory. You might be misunderstanding things here.
This seems like a narrow view given that there are plenty of unanswered questions in chaos theory, etc. but physicists who think about quantum stuff typically don't like to consider the other physics Revolution of the 20th century as equivalent to theirs.
Physicist here.. I will not give Sabine more YouTube views, justifying clickbait titles.
Below is just my opinion.
There are certainly issues in theoretical physics. I think particularly string theory was a massive waste of effort in physics and to some degree illustration of failure of the whole system.
Despite that most of other physics I would say in sensible shape, it is just harder to make progress given that we have to push to higher energies, more accurate measurements etc.
The question whether there will be major advance in fundamental physics to some degree depends on new discoveries. Many people are pushing, but it is not guaranteed.
an analogy with astrology and astronomy fits perfectly.
Remember those great men who did groundbreaking work that completely changed the fabric of society? Consensus my a, their work is self evident. If you need someone to tell you something is a great accomplishment it apparently isn't obvious.
If there is no revolution triggered by [say] relativity theory it doesn't qualify for the list of great discoveries. You need people to tell you how great it is.
Then it's not really all that well made, frankly, because one of the most popular YT physicists is immune to said virus.
But - I have always dismissed cryptocurrencies thinking "people can't be that stupid". If I had not, I could have made some money. So maybe Sophons didn't expect Youtube to be a thing, either.
I'm way too late for this to be meaningful, but here's what I think! tl;dr -- gravity is the problem, we should focus on experiments and observations for a while, bring in some better mathematics, and continue the long range program of developing quantum theories that include or even produce GR.
I'm just a physics enthusiast. When I became interested in physics, I was initially a sort of partisan in the "realist" camp -- pro Einstein, anti Bohr; liked Verlinde's entropic gravity, distrusted the graviton -- but have come full circle to the opposite view. GR has massive explanatory and predictive power, and an extremely satisfying aesthetic quality, but obviously breaks down behind the curtain of a black hole's event horizon, where we cannot make observations. I say obviously because it predicts a singularity, which is just another way of saying it makes no prediction at all. On the other hand, many of my complaints about QM I now look at as unanswered questions, opportunities for inquiry. QM is based 100% on experimental observations. The theory came together in a rather ad hoc fashion at the beginning of the last century, but as it was more carefully studied theoretically and experimentally, also proved to be highly predictive, even more that GR. Yes there are big ugly, outstanding questions -- measurement collapse, the transition from microscopic quantum behavior to macroscopic classical behavior, the intractability of all but the simplest calculations -- but those are huge areas of knowledge that the future will gradually (or suddenly) fill in, as our understanding moves forward.
So, gravity, not QM, is the problem. We should start with the axioms of quantum mechanics, and look for ways to observe where QM and GR can be measured at the same time. LIGO offers opportunities like this, as the sensitivity of the instrument is well within the quantum regime. Continued study of QCD could make a testable prediction for what exists inside of a black hole. Or continue to study the very fine transitions between energy levels in the nucleus. Mathematically, maybe the Langlands program, with its rather weird, Fourier-like sums of L functions will allow us to model non-linear behavior.
And yes, string theory sort of "jumped the shark" at some point. I'm sure Ed Witten regrets saying that other pursuits were a waste of time. But the thing is, the string theory program is centered on QM, and has shown that QM can naturally produce GR, given certain unrealistic assumptions. That's mathematical progress.
> What's even more insane is that the only two people I can think of who have pushed back against this are Peter Woit and Eric Weinstein, and both of them are trying to sell you their own theory of everything
Not exactly. She's just admitted that he isn't someone she thought of. And that's likely because she's far more aware of the contributions of physicists to this field, than the attempted contributions of non-physicists. It's not that she's not aware that they exist - in fact she's painfully aware that there are a great number of them saying all sorts of things - its that she's not individually aware of them.
That said, if she had thought of him then she would have merely increased her sample size from 2 to 3, and still had the exact same conclusion.
What absurd definition are you using that makes Stephen Wolfram not a physicist?
Wolfram is more of a physicist than most physicists.
Wikipedia:
He entered St. John's College, Oxford, at age 17 and left in 1978[17] without graduating[18][19] to attend the California Institute of Technology the following year, where he received a PhD[20] in particle physics in 1980.[21] Wolfram's thesis committee was composed of Richard Feynman, Peter Goldreich, Frank J. Sciulli and Steven Frautschi, and chaired by Richard D. Field.[21][22]
In the mid-1980s, Wolfram worked on simulations of physical processes (such as turbulent fluid flow) with cellular automata on the Connection Machine alongside Richard Feynman[29] and helped initiate the field of complex systems.[citation needed] In 1984, he was a participant in the Founding Workshops of the Santa Fe Institute, along with Nobel laureates Murray Gell-Mann, Manfred Eigen, and Philip Warren Anderson, and future laureate Frank Wilczek.[30] In 1986, he founded the Center for Complex Systems Research (CCSR) at the University of Illinois at Urbana–Champaign.[31] In 1987, he founded the journal Complex Systems.[31]
From 1992 to 2002, Wolfram worked on his controversial book A New Kind of Science,[4][33] which presents an empirical study of simple computational systems. Additionally, it argues that for fundamental reasons these types of systems, rather than traditional mathematics, are needed to model and understand complexity in nature. Wolfram's conclusion is that the universe is discrete in its nature, and runs on fundamental laws which can be described as simple programs. He predicts that a realization of this within scientific communities will have a revolutionary influence on physics, chemistry, biology, and a majority of scientific areas in general, hence the book's title
I don't like Sabine Hossenfelder's videos because they're too short. When I want to relax after work by playing a game while listening to someone drone on on youtube on a deep and esoteric subject, her videos end way too soon, and with an advertisement for her sponsor.
I just want to hear some rambling boffin expound for an hour in the background on some matter that can't possibly raise more than a few hundred views. I decided I don't like popular science videos any more. Boo.
Sean Carroll is my go to guy for long form physics and philosophy discussions that have some depth but are still accessible. His October AMA on the Mindscape podcast is over 4 hours, but I haven't listened to it yet.
"sensational style" is one part but another is that it is hard to extract truth from Sabine's videos, at least for me, not without doing some serious research as someone with a PhD in physics.
Example starting at ~1:00
"Carlo Rovelli is fine with the theory being untestable for practical purposes. So now the situation is that either the theory is falsified or its not falsifiable..."
Is Carlo Rovelli fine with it not being testable, in that he is fine with research continuing even though it can not be tested with up coming experimental set ups? That is reasonable lots of research goes on for long periods of time with out experimental verification. From a funding point of view it makes sense to allocate more money to things that have a tighter feedback loop though. If Sabine was going to expose howe much money was going to these topics and where it could be better spent that would be worth watching.
Or is Carlo Rovelli ok with the theory being unfalsifiable in the sense that that he is ok with the research not being science? This is the straight forward meaning of Sabine's words, but are a negative attack, and one that would come off as a personal attack to many scientists I have known, one that she does not back up with anything immediately and then goes on to make more negative comments like "and Carlo complains to me because he thinks I do not understand his genius".
Ok if Sabine was going to expose Carlo Rovelli as someone who was not really practice science but was getting paid to be a scientist that would be awesome to watch and learn about. That does not happen.
"everyone who works on this just repeats arguments that they all know to be wrong to keep the money coming" - accusation of scientific fraud and defrauding the government.
Ok what percentage and total amount of founding is going to this? Is there anyone who has come forward? It would be awesome to watch something that exposed something like this. That does not happen either.
~3:19 - Arguments saying loop quantum gravity require space to be quantized, but they can not be lorentz invariant without having the quantization go to zero volume, according to Sabine, and no one has done that and extracted back out loop quantum gravity.
I am experimentalist and this is not my area. I would want to see a link to a paper/book etc. The analogy to the angular momentum operator comes off as a good place to start investigation/research but is treated dismissively, anologies like this often do not apply in the end but can still be useful.
3:53 ~ "length contraction should make that minimal area smaller than minimal proof by contradiction"
Ok that does not seem like the gottcha that it is laid out to be. Interesting stuff happens where their are apparent contradictions in physics. If experimental/observational evidence about A produces theory TA and experimental/observational evidence about B produces theory TB and they contradict each other in conditions C that is an interesting point to study look in to etc. This may not be interesting for other reasons, but the apparent contradiction does not make it obviously non interesting.
~4:27 ~ "this can't work because these deviations would inevitably so large we'd have seen them already" -
Why did Sabine talk about it being a mathematical contradiction if you can make the theory work, but it leads to physical phenomenon that we do not observe?
I can not make those two arguments jive in to a cohesive whole. Not that it can not happen, but I can not from this video and that is the conclusion, or similar, I normally reach when watching Sabine's videos and why I do not watch or recommend them generally.
I do not see any of the interesting things I mentioned above being discussed or dug into in comments so far or other new interesting takes. The issue for Sabine's videos, at least for me, is not the "sensational style".
Well, if you want a simple argument from authority, John Carlos Baez's confirmation that she's right is pretty good. If you want a better one, she very rarely gets any of her facts wrong.
Now let's go point by point.
Is Carlo Rovelli fine with it not being testable, in that he is fine with research continuing even though it can not be tested with up coming experimental set ups? He is arguing for a version of the theory that can't be tested, is continuing to do research on it, and presumably thinks that he is doing science.
If Sabine was going to expose howe much money was going to these topics and where it could be better spent that would be worth watching. Discussing how these things wind up getting funded would be a very different video. And would not likely be interesting to most of her audience.
Or is Carlo Rovelli ok with the theory being unfalsifiable in the sense that that he is ok with the research not being science? Presumably he thinks that he is doing science. Sabine's opinion clearly is that this isn't really science. However she only claims her opinion as her opinion, not established fact.
Ok what percentage and total amount of founding is going to this? Again, that would be a very different video. In 10 minutes for a general audience, you have to make decisions about what you will and will not cover. It's not a valid criticism of her that she made a choice. Particularly in a video that she disclaims as a personal rant.
Arguments saying loop quantum gravity require space to be quantized, but they can not be lorentz invariant without having the quantization go to zero volume, according to Sabine, and no one has done that and extracted back out loop quantum gravity. This is not according to her, this is according to an argument that comes from Lee Smolin. A region of space that has a specific amount of area will, according to special relativity, have a smaller area according to an observer that is traveling fast enough. By having the velocity as close as you want to C, you can make the area arbitrarily small. So your choice is to violate Lorentz invariance, or have arbitrarily small areas. If you violate Lorentz invariance, the speed for light will depend on the wavelength.
As her previous video at https://www.youtube.com/watch?v=ZlHvW6k2bcM said, this prediction of Lee Smolin has been tested to extremely high precision, and the predicted effect was not seen. That version of LQG has been falsified. The alternative supported by Carlo Rovelli is that you need to average out over quantum areas in all reference frames. This is a neat idea, but in several decades, nobody has made it work. Until someone can make it work, LQG can't produce any testable predictions.
Please note that John Baez, who worked on LQG for 10 years, specifically complimented her presentation of this particular issue. Her description of where research stands is accurate.
I am experimentalist and this is not my area. I would want to see a link to a paper/book etc. Rants generally do not come with properly cited references. That said, the previous video that this refers back to is based on https://arxiv.org/abs/2402.06009?utm_source=substack&utm_med..., which is one of the experimental tests showing that Lee Smolin's prediction is false.
The analogy to the angular momentum operator comes off as a good place to start investigation/research but is treated dismissively, anologies like this often do not apply in the end but can still be useful. It was a good place to start. After 20 years of research that has failed to turn that idea into anything workable, most people would conclude that this is an analogy that will not apply in the end. But apparently Rovelli gets mad at anyone who doubts that it will work out. One of the triggers for this rant was whatever Rovelli said to her in private. Personally, I excuse her for being human here in her reaction.
Ok that does not seem like the gottcha that it is laid out to be. Interesting stuff happens where their are apparent contradictions in physics. No, it really is the gotcha it claims to be. It's directly inside of the math. This demonstration is no different than, say, proving that sqrt(2) is irrational by proving that if you start with the smallest fraction that equals it, you can find a smaller one.
The conclusion of that gotcha is exactly what she said: if there's a minimal area then you can't have Lorentz invariance. And conversely, if you have Lorentz invariance, then you can't have a minimal area. Experimentally, we have tested for the Lorentz invariance to be expected from a minimum area based on the Planck length. It does not exist. And therefore there isn't Lorentz invariance.
Why did Sabine talk about it being a mathematical contradiction if you can make the theory work, but it leads to physical phenomenon that we do not observe? Her previous video (that triggered the nasty emails)_made this point more clearly. She's saying that there is a mathematical contradiction between having minimal areas and Lorentz invariance. This forces us to choose to have one or the other. Minimal areas leads to a testable and now falsified theory. Lorentz invariance has yet to lead to a theory that doesn't blow up with unnormalizable infinities, let alone one which can produce a testable prediction.
I can not make those two arguments jive in to a cohesive whole. Not that it can not happen, but I can not from this video and that is the conclusion, or similar, I normally reach when watching Sabine's videos and why I do not watch or recommend them generally. Is that Sabine's fault, or yours? This video is much lower quality than her normal ones. And yet absolutely none of what you think are flaws, do I think is one. Every one of your objections has an answer that jives. And the conclusion is agreed with by John Baez, whose background on this specific topic is much stronger than yours.
Perhaps, rather than looking for things to complain, you should try figuring out what she actually said. In my experience it is logically internally consistent. Even though it skewers some sacred cows.
In other words, "she said something that completely contradicted my prejudices and the cognitive dissonance was uncomfortable, so I memory-holed what she said and immediately dismissed her claims as non-factual and avoid her from now on because I never want to experience that dissonance again".
She was ripping on the valuations and economics of quantum computing companies the other week, and her critiques were such that they could be levelled against capitalism itself and basically any company in the market. Was an obvious and clear step way out of her area of expertise.
That doesn't have anything to do with her criticism of Loop Quantum Gravity, and is precisely the derailing of the topic that dang is asking you to avoid.
yeah. she does seem like she's on the edge of throwing down f-bombs, flipping tables and screaming "i'm out of here." guess it's to her credit she hasn't done that.
I've said this before in not the same words, and I am always downvoted here on hackernews: people need to understand theory of knowledge before they understand science. Physics and physicists are the worst offenders.
This strongly depends on what you mean by "theory of knowledge".
If you mean the practical importance of self-honesty, and a historical awareness of how easily we slip into self-delusion, then I agree. See, for instance, https://calteches.library.caltech.edu/51/2/CargoCult.htm for a very famous speech on exactly this topic. A lot of Feynman's writing touches on the same issue.
If you mean the musings of philosophers on epistemology, then I emphatically disagree. The philosophers in question generally have failed to demonstrate that they understand science. And when they venture into science, they generally fail to live up to the ideals that they proclaim that scientists should follow. As an example I direct you to the sight of Karl Popper arguing to the end of his days that quantum mechanics cannot be a correct scientific theory. An opinion that began because a probabilistic theory cannot in principle be falsified.
In fact QM is a scientific theory, and it stands as an example falsifying Popper's criterion for science!
I find it very ironic that Feynman is so disliked by philosophers for having been honest about how irrelevant they are to science. And philosophers in turn have failed to recognize Feynman's explanations of how to do science as a key topic that should be included in any proper philosophy of science.
I'm in the Popper camp on your example. You may have good reasons as to why you say he's wrong, but isn't that the scientific method: showing things to be false. If it can't be shown to be false then how can it be scientific? It might be some other branch of thought.
On the specific case of quantum mechanics - I want to see these forever promised quantum computers actually doing something useful. The promises went from (Vs classical computers) they will do everything faster, to they will do some things faster, to they will do some things not achievable at all. And yet, they still haven't done anything as far as I can tell. Physicists need to answer honestly for this.
If by "theory of knowledge", you mean they need to have read a bunch of philosophical musings on epistemology, then I strongly agree with the downvoters, because that's utter nonsense. If you mean anything else by that, then you're being way too vague to contribute to a technical discussion, so again I agree with the downvoters. Try defining what you mean by "theory of knowledge" and explain why you think that's required to "understand science" (and you might want to explain what you mean by that too) and I suspect you'll see a lot fewer downvotes.
Theory of knowledge "is a branch of philosophy that examines the nature, origin, and limits of knowledge". Scientists need to understand the limits of knowledge which may be acquired by science.
Scientists think they are in the unique possession of tools which ascertain truths - this is misled.
Amusingly, the International Baccalaureate Diploma Programma - an A-Levels like uni-prep course - has a subject called TOK: Theory of Knowledge with these intentions.
I have a pet conspiracy theory for why there has been so little progress in physics for so long. The invention of the nuclear bomb scared a lot of people, it made them scared of physics. What else might physicists turn up that could change the world in dramatic ways? Anti-gravity? Ray guns? Other dimensions? Travel to other worlds? All bad for business, no one is going to buy your airplanes or air craft carriers if they can buy an anti-gravity machine. So physics was suppressed by both business and government. Physicists were given "safe" work to do (ITER, quants) that would occupy them and keep them from exploring wild stuff. Grant financing was controlled so that only safe research would be conducted. It would be fairly invisible to the world, just a few high level decisions would determine how the funding was directed. I get the impression that if this was indeed a conscious decision that it's starting to fall apart as younger generations take over and become frustrated with the direction of physics. They weren't there when the A-bomb was invented, and nuclear weapons have not been on peoples minds much for a long time, most people have not lived in a time when one was used. So they see interesting topics and want to explore them and encounter resistance from more established scientists. It's a conspiracy theory because it would involve some buy-in from a fair number of physicists to make it work, but a lot of physicists when I was getting my BA in physics were very loudly saying "never again" about atomic weapons and felt it had tarnished the whole profession. It's very difficult to say what humanity would be capable of handling in terms of radical new inventions. Anti-gravity could solve many large problems, but it might make it even easier to destroy Earth. Once new knowledge exists it is hard to suppress it. Stopping it from from ever existing seems easier. I guess we'll find out if physics has been suppressed if the dam breaks and new ideas start proliferating. The nature of the new physics would be a big clue as to whether research in it was suppressed. I'm reminded of Elon Musk, he seems to have had really radical success in some very stagnant industries, just by trying instead of accepting limits, and being able to fund his ideas himself.
The theory stops working imho if you take competition into account. The world is not aligned as a single bloc of power. While it’s not completely unthinkable (but extremely unlikely, imho) that some scientists plus some decision makers from, say, the liberal west might collude to achieve this kind of suppression, their counterparts from one or multiple other blocs might not, because they want to dominate and anti-gravity guns surely give you some nice advantage.
The desire to dominate can take a weird turn if using your anti-gravity guns reveals them and makes it likely others will soon invent the same. There is precedent for this, say in electronic warfare or cyberwarfare. As soon as you reveal your uber virus, anyone can take it apart and modify it for their own purposes. So you don't reveal it except as a last resort. Competition doesn't come into play then, everyone hides their secret weapons and never uses them unless they have to, and tries to make sure information in that area is suppressed. However, as I say in other comments, this may have been a bottom up conspiracy, not a top down conspiracy, though it may have moved to the top as the scientists themselves gained power. But the fear would still exist at all levels; sure your anti-gravity gun gives you an advantage, but what if it eventually causes random micro black holes to appear near where you use it, obliterating infrastructure before evaporating? We just don't know what the repercussions of new technologies will be, and while the risks have seemed low in areas like software, the risks seem higher with fundamental new physics. People are historically pretty bad at predicting how technology/science will play out in the long term. AI was a joke for a long time, until it wasn't. The internet was hailed as revolutionary, but it seems very different than it did in the year 2000. It's a lot like computer security, you can imagine the possibilities, but you probably can't imagine ALL the possibilities. It takes time and collaboration to scope out what it is that is new that can now be accomplished. That uncertainty scares some people and excites others. Seems kind of like walking through a minefield littered with Christmas presents. Some people might decide to leave the presents where they are.
There are some good comments here, thanks! There has been an international component to physics research cooperation. It seems not inconceivable that physicists in many countries, meeting at paper conventions and such might have agreed and recruited each other to try to prevent the next atomic bomb type invention. So while competition between countries is certainly real, competition between scientists might be somewhat different. You'd think there would be some people who would pursue it regardless, but they'd probably have to work with a team, and not everyone on the team may have supported the goals. It's just a theory, but it has some plausibility. Perhaps there are people everywhere who have decided not to be part of endeavors that could be disruptive and they've done us all a favor or have kept us from discovering the secrets of the universe. Who knows? The ethics of science has been mostly left to chance and individual decisions.
An easier theory is that the Standard Model is so good that it's very difficult to find anywhere it fails. So there's no experimental fuel to propel physics forward.
What time frame are you talking about here? Starting in 01950, 01995, 02010?
If we're talking about 01995, it's conceivable that, say, the US and CERN could coordinate to suppress research into hafnium bombs, AVLIS, antigravity, or whatever. If we're talking about research much prior to that point, though, you'd have to include the Russians in the conspiracy. Probably not just any Russians, either; probably Khrushchev, Brezhnev, Andropov, Tsar-Bomba-era Sakharov, and his successors. And, on the other side, people like J. Edgar Hoover, JFK, McNamara, Kissinger, Johnny von Neumann, and Teller.
I don't want to say it's literally impossible for Brezhnev or his underlings to have made a secret agreement with Kissinger and Teller to suppress the development of theoretical physics in order to keep the world predictable. But I do think it's pretty implausible, and there would have been an enormous incentive to cheat on any such secret agreement.
In the 01990s, though, it could have become plausible. But, remember that that's also when Pakistan became a nuclear weapons state, shortly followed by North Korea in 02006. And the People's Republic of China has had nuclear weapons since 01964, so they evidently had significant physics capabilities that they were willing to use for warfare (which was a huge priority; Mao reorganized the country's economy to resist an anticipated US invasion), and they dominated the TOP500 supercomputer list until this year, when they withdrew from it in apparent protest against the efforts of the USA to reverse their technological progress with a worldwide system of export controls.
So I think there's maybe a ten-year window when this could have happened somewhat, about 01992 to 02002. Both before and after that, there are too many countries with strong physics communities that are too bitterly opposed to make such cooperation plausible.
Reading the comments here my thinking has been revised. I'm no longer suggesting the elites were conspiring, at least initially, I'm suggesting the physicists were conspiring for ethical reasons. Some of them may have moved up the ladder and reached positions of some power. Physics is magic to most people, hiding possibilities in math and technicality seems possible. Anyone who has written code professionally has probably been faced with similar decisions, biases can be encoded, and you have to decide how you are going to approach these things. For example, do you add a race field to the medical database or not? In 1990 it was often left up to the programmer. Sometimes things are decided far below the level of the people running the show. Regardless, I do think my theory is far fetched, innate curiosity seems likely to have caused some people to explore further regardless of the risks, and an overt conspiracy that eventually reached high levels seems likely to have been soon discovered.
Quite astounding, he seems to have been both woke in some ways (climate change) and fundamentally misguided. I can see a lot of Trump's playbook in his life. I was imagining a much more passive conspiracy, people refusing to participate for ethical reasons, rather than an elite conspiracy by the Venutians/Illuminati. The video seems unintelligable, he makes so many references to obscure history that may or may not be true (and how would he know?) it becomes meaningless without years of research and even then, the intentions and thoughts of historical figures are difficult to ascertain.
Theoretical physics are theoretical; that seems to be the crux of her problem. And in that light it makes sense that she's become an influencer who makes content instead of someone who devotes most of their time to advancing the science. Yes, oftentimes people will be paid to work on problems, and they'll end up in a cul-de-sac. That will be the case for the majority of the field in the case of something like quantum physics. But if we pay enough of these people to sit in rooms and work on problems, maybe one of them will figure something out. That's how science progresses.
I think that you have half a point. You're absolutely right that just because people are paid to think about things, doesn't mean that they are making progress. And there is a lot of evidence that this is true today in the foundations of physics.
However string theory was not intentionally untestable. In https://www.youtube.com/watch?v=eRzQDyw5C3M she gives a good history of why it was originally invented, what testable predictions it made, how it failed those tests. And then how string theorists who were trying to find relevance for their work tried to keep it going as it stumbled into being untestable.
Exactly. Consistently untestable and unfalsifiable claims for decades has to be seriously questioned at some point, and I think we're well beyond that point. This is especially true for string theory. I'm particularly fond of how Angela Collier laid out the timeline of string theory in her video on it[0] as well as the consequences that science communication is now facing as a result.
How is it "intentionally untestable"? I get that it is practically untestable, but as far as I know, there are people working to try to find some possible tests.
For the context, the video this is a follow up to is helpful (they're both short) - https://www.youtube.com/watch?v=ZlHvW6k2bcM
John Carlos Baez thinks Sabine has a point.
https://mathstodon.xyz/@johncarlosbaez/113285631281744111
>Despite the silly clickbait title of this video, Sabine says a lot of interesting stuff in it: her criticism of claimed deviations from Lorentz invariance in loop quantum gravity is about as good as you'll get from anyone who hasn't actually worked on loop quantum gravity. I worked on it for about 10 years, and the situation is even a bit worse than she makes it sound.
I know people have strong reactions to her and her sensational style, but that is a serious recommendation from a knowledgeable person, so I think we can give this thread a second chance. (Someone emailed and asked us to.)
All: please let's keep the comments on topic and substantive (and avoid the sensationalism and personality aspects).
Edit: this subthread was getting too off-topic so I moved the replies to https://news.ycombinator.com/item?id=41814764. Feel free to reply there if you want.
30 years ago I spoke to a fairly well known and regarded physicist who said something rather interesting along the same lines. Quoting as accurately as I can "physics looks sexy from the outside due to some celebrities but inside it's mostly worse than anyone wants to admit.". He also suggested I go and study mathematics instead because at least there will likely be some applications for it. I did and I am glad I did.
Sounds like this criticism would be valid for fundamental physics but there are many other physics fields with experimental results that become technology.
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IANAP but it seems that fundamental physics suffers from a lack of monotonicity of knowledge. Although physics does its best to explain things, those explanations are more like guesses than known facts. A theoretical physicist can have their life's work undone simply because someone else comes up with a better guess, or experiment says no. You spend your life working on SUSY and then... nope. Even very established knowledge can be overturned.
People will say "that's science" and indeed that's fundamental physics, but other fields don't really work like that.
In chemistry and biology, certainty isn't in such short supply. Nobody is asking "but is DNA a double helix?" Researchers take a problem, they attack it, then they publish the results, it gets replicated (or not), and the set of knowledge grows.
Mathematics is more similar to chemistry and biology insofar as mathematical knowledge takes the form of an ever-growing set of proven facts generated by research. Take a problem, prove it, other mathematicians check it, the set of knowledge grows.
Fundamental physics has issues because the "check" stage now often costs millions or billions of dollars (build a particle accelerator, neutrino detector, gravitational wave detector, satellite, etc), and even then it might not give a definitive answer. Just look at the g-2 situation where they notice a discrepancy, they spend millions of dollars trying to determine if this single discrepancy is real, and then someone publishes a paper "haha I recalculated it, you just wasted your time".
Not a criticism of fundamental physics because clearly that's just how it is. I'd rather have guesses than ignorance. The gravitational wave research seems to be doing okay at least.
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> John Carlos Baez
For those like me who didn't know, https://en.wikipedia.org/wiki/John_C._Baez
> John Carlos Baez (/ˈbaɪ.ɛz/;[2] born June 12, 1961) is an American mathematical physicist and a professor of mathematics at the University of California, Riverside (UCR)[3] in Riverside, California. He has worked on spin foams in loop quantum gravity, applications of higher categories to physics, and applied category theory. Additionally, Baez is known on the World Wide Web as the author of the crackpot index.
He was also a long-time maintainer of the Usenet Physics FAQ and has been writing about physics and mathematics on the internet for decades. So not only is he the real deal in terms of knowledge, he also has a long history of communicating that knowledge to the public, albeit typically for a more advanced audience.
He is better known within physics as the author of This Week's Finds in Mathematical Physics, an archive of which is at https://math.ucr.edu/home/baez/TWF.html. His more current blog is available at https://johncarlosbaez.wordpress.com/.
And https://news.ycombinator.com/user?id=johncarlosbaez!
Perhaps he'll contribute to this thread (or perhaps it would waste his time)
And he was known on Usenet and sci.physics before the World Wide Web was invented...
I'm not hot on what fundamental physics looks like now or in the future, but there's an attitude that Sabine promotes that I see echoed in a lot of comments here which feeds into problems with research.
I don't think the work put into studying fundamentals was "a waste of time" thus far. It's dangerous to label experiments and ideas that were acted on in good faith as the best options at the time but didn't yield positive results as missteps.
Scientists need to be allowed to do work like this without fear because to do so otherwise leads to perverse incentives and you end up with things like lots of studies that can't be reproduced because of p-hacking or worse.
Arguing bad faith after the fact is awfully hard without real evidence and if you're going to discount anyone with enthusiasm for their research proposal based on enthusiasm alone you're not going to be left with a healthy program. I don't blame anyone who supported things like supersymmetry as an example for something which hasn't panned out. we're still left with a major mystery and big questions and it says we need to rethink things in more difficult directions.
The whole of human society is a combustion engine for life, barely held from going full self destruction by a science driven economy consuming resources in a unsustainable way. Science is what kept us peaceful and nice since WW2. And the breakthroughs are needed not some time far far away ,they are needed now. This is not about the purity of approach or some hypocritical game. This is a dependancy of life and death on the results ..
I'm not in any way an expert in this area, but here is what I see. I don't think the argument is that it's being said as "bad faith after the fact". I think the argument is that the approach was told it had fundamental flaws. Those were ignored / denied. People continued to invest in it and suck up all of the research and bright minds in the field. Decades later it still has those fundamental flaws and has taken over all other possible avenues of progress as it has all grant money and and the majority of all departments working on it.
It's more "you were told this is broken before. It's decades later and it's broken in the same way. At what point to you admit that this approach isn't working so try something else?" And the answer is "No, we're going to keep digging deeper".
Fundamentally, approaches need to be falsifiable. If your theory is "falsifiable" in the small scale but ultimately unfalsifiable in the large scale then it's is fundamentally unfalsifiable and we can't use it to lead experimentation.
It's a breadth vs depth search question. We've lost all breadth of search in physics, because a little ways back we stumbled upon a branch that happened to have a (for practical purposes) infinite number of subbranches relating to ways to roll up string dimensions. So physics is stuck exploring all of those sub-branches instead of backtracking one level and exploring any other parts of the tree.
The argument is that everyone is looking under the lamppost for the keys. After 4 decades of searching there, maybe it's time to search somewhere else. And the argument is made even strong when decades back they were told, "Hey, I didn't drop by keys by the lamppost. I dropped them somewhere else". And yet most people keep looking there.
Sabine's argument has been frequently bad faith after the fact and currently. Just skimming some of her written work:
"Before the Large Hadron Collider turned on, particle physicists claimed that it would either confirm or rule out supersymmetry. ... The answer is that the LHC indeed did not rule out supersymmetry, it never could."
https://backreaction.blogspot.com/2022/04/did-w-boson-just-b...
"I hope they’ll finally come around and see that they have tried for several decades to solve a problem that doesn’t exist"
https://backreaction.blogspot.com/2018/02/what-does-it-mean-...
Here she says physicists will just keep building bigger colliders because they can and not on merit
https://www.scientificamerican.com/article/the-world-doesnt-...
Here she said CERN's push for an FCC is "full of lies"
http://backreaction.blogspot.com/2018/12/cern-produces-marke...
When people are accused of ignoring or dismissing credible points where a program is legitimately problematic is exactly an accusation of operating "bad faith". "Good faith" means doing legitimate and believable science with the best information. These are claims it was done to the contrary.
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My understanding of the situation (which may be wrong, in which case please let me know) is that physics is stuck at a local optimum.
There are two obvious ways to get out
(1) Surprising physical observations, or
(2) Mathematical advances
Way (1) is what kicked off quantum mechanics. Way (2) is what kicked off Newtonian mechanics.
I see string theorists and loop quantum gravity people as working on (2). Their models are mathematically interesting and aren't totally understood from a mathematical perspective. But they're different enough that studying them may break the impasse.
I see (1) as largely limited by the budgets and technology needed to build things like particle accelerators and spacecraft.
For (2) you have to decide whether to only explore mathematics that defines physical reality, or whether to also allow exploration of non-physical systems. For example, you might explore a universe that is almost physical but has time machines. Restricting the search space to only physically realistic systems is a significant constraint, so there's a debate to be be had about how much weight to give it.
> physics is stuck at a local optimum.
I think I heard somewhere that the trouble with string theory is it can describe anything if you tune it just in a right way. It reminds me of epicycles, they also had this property, you can add more and more epicycles to describe literally any observation data.
> Way (1) is what kicked off quantum mechanics. Way (2) is what kicked off Newtonian mechanics.
Hmm... What was the way that kicked Copernicus to redraw epicycles with the Sun in the center? I mean, is there some notes on these? For example, Newton took as granted that celestial bodies move by elliptical orbits, and somehow he guessed that the gravitation law has r^2 in its denominator, and so he invented calculus to prove, that if you have r^2 in the denominator then you'll get elliptical orbits. The question where Newton got his guess it remains open for me, but back to Copernicus, what was his way?
Maybe he thought how movements of planets will look if seen from the Sun, and so he had redrawn epicycles to take a look, and he got circles? (I'm not sure that it could work this way, I propose this answer to my question just to give an example of the kind of an answer I'd like to have).
I ask this question for two reasons.
1. I believe that Copernicus advanced the science not with surpising physical observation and not with mathematical advances, to me it seems more like surprising mathematical observation. I'm not sure what was that observation exactly.
2. Can one apply techniques of Copernicus to the modern physics? I suspect that it will not. I'm sure physicist already tried everything and there were (is) a lot of them and they are pretty smart people, so it is highly unlikely that Copernicus can help them in any way. But I'm still curious, what Copernicus would do? Would he tried to imagine how electron flying through a double-slit might observe scientists-observers? Or maybe it would try to feel the pain of a black that may believe that the whole universe is falling on it? I bet that the true Copernicus idea would require to use some pretty hard mind-altering substances, and I like such ideas.
Copernicus used the same circular-orbit-plus-epicycles system as Ptolemy, just the orbits were centered around the sun (kind of---each planet had its own circle, with the sun only approximately in the middle). The system actually had more epicycles than Ptolemy's and was less accurate. It wasn't an advance in any meaningful sense.
The real breakthrough was Kepler, who dropped the idea that planets moved in circles. It was indeed partly a mathematical breakthrough and the reason Kepler's work took a while to catch on is that people couldn't understand his math at first. But it was also empirical, as Kepler had access to new and much more precise observational data collected by his mentor Tycho Brahe.
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Before Newton, Kepler already figured out that orbits were ellipses. Newton figured out why orbits are ellipses.
My understanding as a layman:
1. Copernicus figured out that if you put the sun at the center, then epicycles weren't necessary, and the math got easier --- because epicycles were based on a mis-understanding of the actual state of the universe --- I don't believe that anyone has identified such a non-alignment of fact and reasoning and observation for contemporary physics.
2. The problem is, modern physics is arguably getting boxed into a corner by approaching an end game state where the fundamental particles are getting identified, but are so small and difficult to separate out, that measurements are challenging to the point that while one can speculate and do math, actually proving out the speculations experimentally and taking actual measurements is expensive or so difficult to reason about that there doesn't seem an obvious path to an experiment, e.g., it looks as if the electron may be a fundamental particle, which is a sufficiently difficult concept to parse that it led to "The one-electron universe"/"The single electron hypothesis" and if that is the case, it walls off a not insignificant portion of particle physics at a size/state which can't be gotten smaller than.
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I can probably answer the r^2 question: it’s the scaling associated with the surface area of a sphere. So if you have light source, or a sound source, that’s how it scales with distance. It would have been relatively simple for someone as smart as Newton to guess that gravity worked the same way.
It’s only really our current understanding of gravity that makes it unobvious.
Everett proposed that observation happens relative to observer, it's exactly Copernicus's observation. Some people buy it, many don't, so I guess heliocentric style thinking is still counterintuitive. Ironically, an argument against Everett's interpretation is the same Aristotle used against heliocentrism: "it's not supported by observation" (meaning relativity is unobservable).
Those mathematical advances weren't developed in a vacuum, but made to solve some very specific problems which came from better measurements. So even Newtonian mechanics originated in solving problems trying to explain measurements, not that someone sat in their chamber and dreamed up cool math that happened to be very useful.
Number theory and algebraic geometry were developed for their own sake (i.e. "it is cool"), but later people found practical applications in cryptography.
So "useful math must be motivated by practice" is empirically false
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I agree.
Generally, the scientific method has mutually recursive turns of theory and observation. And I don't mean to imply that exist independently.
I'm just saying that if you get stuck, the two clearest ways out are to provide more observations or perturb the theory.
Name a single physics phenomenon that was discovered purely with way 2. I can only think of one, the positron.
Newtonian physics was not kicked off by math "advances". Approximately speaking it was the other way, Newton created the math to explain p^2 ~ r^3, which was a surprising observation.
Even theory of relativity wasn't really a math advance, the math was already mostly worked out by mach, lorenz, and minkowski. Einstein put it together into a coherent story (v. Important)
Bose-Einstein statistics, which originated purely from finding a derivation of an equation, without immediately understanding of the true physical meaning of the derivation.
And then Bose-Einstein condensates; a thought-experiment consequence of Bose-Einstein statistics.
Radio waves etc., from formulating Maxwell's equations.
The Higgs.
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(1) is also limited by imagination
Isn't it (2) that's limited by imagination? Nobody imagined quantum theory, they observed it first.
This might be too weird to be true, but when I heard that Geoff Hinton got the Nobel prize for Physics, I wondered if the prize committee was having trouble finding "real" physicists who had made fundamental advances....
This is not meant to knock Prof Hinton. These are his own words:
“I’m not a physicist, I have very high respect for physics,” Hinton said. “I dropped out of physics after my first year at university because I couldn’t do the complicated math. So, getting an award in physics was very surprising to me. I’m very pleased that the Nobel committee recognised that there’s been huge progress in the area of artificial neural networks.”
It is evident that they need more than five categories. Awarding Nobels to individuals who are not particularly (if at all) well-versed in the subject at hand, even if they contributed to a breakthrough in the field, directly or indirectly discredits the prize.
Indeed, the online memes about Hinton and Hassabis being "a bit of a <physicist|chemist> myself!" are justified, in my opinion.
I agree with you. What is also telling is that there is no particularly strong reaction from the physics community that someone obvious was wrongfully omitted.
> What is also telling is that there is no particularly strong reaction from the physics community that someone obvious was wrongfully omitted.
A few days before the announcement of the Physics Nobel Prize Sabine Hossenfelder created a video about her predictions for the Physics Nobel Prize. Likely all mentioned researchers in this video did more for the advancement of physics research than John Hopfield and Geoffrey Hinton:
> Who Will Win This Year’s Nobel Prize in Physics? My Speculations
> https://www.youtube.com/watch?v=KMTNHqEpTnw
If LQG turns out to be unworkable, we're back at string theory as the only renomalizable description of quantum gravity.
Quantum gravity research amounts to one professor per university faculty on average. Even in the worst case this would not be the crisis of unmet expectations it is made out to be... QG researchers are very brave because they are risking everything on the possibility that existing data constrains quantum gravity in a way that hasn't yet been understood. I doubt there is even a single person making that gamble unaware that the Planck energy density is something like 20 orders of magnitude above present-day experiments.
> we're back at string theory as the only renomalizable description of quantum gravity.
I think you mean, we're back at "we're not sure if string theory is a viable theory of anything real".
Quantized gravity is not necessarily the right answer, and an insistence on this fundamental assumption might be the origin of these difficulties, eg. see Oppenheim's semi-classical gravity.
The fundamental reason for this is simple. Humans are prone to cognitive dissonance. Meaning, we do absurd things to avoid painful thoughts. And anything that questions our sense of identity, is a painful thought.
So if my self-image is, "I've advanced our understanding of the fundamental nature of reality," then the idea that my contributions weren't useful becomes painful. So we avoid thinking it, challenge people who question our past contributions, and so on.
The natural result of this cognitive dissonance is a feeling of undue certainty in our speculations. After all certainty is merely a belief that one idea is easy to believe and its opposites are hard to believe. We imagine that our certitudes are based on fact. But they more easily arise from cognitive biases.
And this is how a group of intelligent and usually rational people descend into theology whose internal contradictions can't be acknowledged.
This is beautifully articulated.
And reinforces my general below-the-line (layperson) fear about the state of physics today (as reinforced ofc by the likes of Sabine Hossenfelder & Eric Weinstein).
Thank you for the compliment.
I've been working on how to formulate that idea clearly for a while. It is a problem that goes well beyond physics. For example I believe that the same cognitive error is behind the fact that experts do significantly worse than chance in actually predicting the world, and the more certain the expert sounds, the less likely they are to be right. See https://www.amazon.com/Expert-Political-Judgment-Good-Know/d... for data demonstrating that fact.
Depressingly, this means that we consistently put public policy in the hands of people who are demonstrably incompetent.
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To extend this, group dynamics can come into play too.
I once worked at a startup that developed fancy new tec. The group dynamic there was that critical thinking absolutely did not exist. The reason was probably that they accepted only people in their circle, that had the same burning positive attitude towards the idea.
This can become a self reinforcing circle, because critically thinking people will leave at some point. (Like sabine did in physics).
Off topic, but a bent towards irrational optimism is necessary for progress. Generally, positive bias is needed for good mental health.
Probability shows that your idea will almost certainly fail, but you can’t believe that and put in the necessary effort to make it succeed.
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> So if my self-image is, "I've advanced our understanding of the fundamental nature of reality," then the idea that my contributions weren't useful becomes painful.
Only if one believes the logical fallacy that the dependent steps of a process of elimination weren't useful.
Even if you believe that they are useful, you're also not going to wind up as a hero in the history books. And so people wind up acting in the same way.
Besides, the argument that all of the bad ideas contributed to discovering the right one, is as strong as the empirical argument that white chairs are evidence that all ravens are black. Logically you're right. Discovering the right idea requires disproving all of the wrong ones. Similarly "all ravens are black" is logically the same as its contrapositive, "all non-black things are not ravens". It's just that you've just decided to focus on a search space that is so much bigger, that each data point in it becomes much less important.
Eh, in many ways the problem is a sunk cost fallacy type issue.
If someone is later in their career and looking at having to throw away all that time - time they will never recover - it takes someone really special to just do it.
And by really special I mean ‘kinda suicidal sometimes’.
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It's in the video: LQG is not a promising, or even a plausible, physical theory. That's the idea.
"Don't be snarky."
"Please respond to the strongest plausible interpretation of what someone says, not a weaker one that's easier to criticize. Assume good faith."
https://news.ycombinator.com/newsguidelines.html
(I'm sure you could rephrase your point here as a substantive thought in a respectful way and then it would be fine)
This is where climate skepticism comes from by the way. Even climate skeptics will acknowledge that climate scientists are well educated, they don’t deny science as a process of truth seeking, the problem lies in the incentives.
There’s a lot of prestige and grant money that comes with insisting climate change is true.
There’s a lot of political power that gets ceded to the people in charge if we “just accept that we’re in a crisis and us elite are the only ones that can stop it”.
I believe climate change is real and human caused, but many of the claims and doomsday speak feel like self interested humans following their incentives beyond the scientific truth
What are you talking about? I spent years munging climate datasets from various research institutes around the world. The upshot: it doesn't look good for humanity. I seriously don't understand how a neutral third party can walk away from this climate work and think, 'Nothing to see here folks.' The denialism and willful ignorance of the potential catastrophic consequences is something I find terribly disheartening. Mark my words - the temperature records that keep getting broken year after year are going to keep getting broken. Entire towns going up in flames and cities being wrecked by increasingly more powerful hurricanes will be the new normal. <sigh>
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You know how some people seem knowledgeable until they talk about your field? Well for me (molecular biology and genomics) this never happens with Sabine.
So, even though much of this is over my head, I grant her much credence.
FWIW.
I think the problem is more fundamental. Newtonian mechanics is a science based on observation. Mathematics is just used to build a model that describes _how_ the reality behaves, not why.
Now Einstein is very special, because he proved that our human perception of space and time is wrong. When we think about the allegory of the cave, we got a glimpse of the reality we couldnt see before.
Nowadays every phyiscist wants to be the next einstein that uses mathematics to show us something about reality. The problem is that einstein had good reasons for his ideas. The constant speed of light didn't really work with maxwells equations. The model at that time didn't correctly describe the observations and the maths he used to solve that is rather elegant and simple.
Her choice of background for this video and the matching imprint on her blouse gives us maybe a hint that "fundamental" physics is too broad a field to actually die :-) I.e., there are ongoing and deep puzzles e.g., in dark matter / dark energy where observational data keep accumulating and at some point a critical mass (pun) of evidence may reshape our ideas about how the universe fundamentally works. The new ideas need have nothing in common with pre-existing mind sets of how things work.
Now about the string theory / quantum gravity furore, after decades of work by arguably extremely bright people its pretty clear that Nature in the current juncture is not giving us enough clues to proceed. This should not be stressful - Nature is not a Hollywood production studio that needs to churn gee-wow "experiences" every season. But Sayre's law applies rather well [1] "In any dispute the intensity of feeling is inversely proportional to the value of the issues at stake.". What is at stake here is the ego of a few individuals that assumed otherwise (i.e., that a post-Einstein revolution is imminent) and the (relatively minor in the scheme of things) research funding of this particular niche of physics.
Theoretical physics is not the only domain bouncing regularly between "hypes" and "winters", as the recent Nobel prize for Physics clearly demonstrates.
[1] https://en.wikipedia.org/wiki/Sayre's_law
I know that this will probably be down-voted to death but I don't like these hyperbolic takes. I know that Sabine did use this title for click-bate purposes that she is now mostly doing YouTube videos (she had horrible experience that unfortunately not rare in scientific community [1]). I understand that the field of particle physics which is the corner stone in fundamental physics is not showing the great advances that it used to have a couple of decades ago. But I think people really don't understand that the field is still advancing and although these advances are less catchy to be reported in mainstream (and don't get traction if posted on HN) it is not dead or dying.
There is a reason why we had a particle data group updating the PDG [2] each two years (you can order physical copies for free but please don't do if you don't need one). People were writing about that since after the big discovery of Higgs boson (that was 12 years ago). We still have a lot of measurement and puzzles that is less about unification theory that people usually would talk about. Theory people are coming up with all different ideas even if some are not testable now but that job of theorist is mainly come up with ideas and help bridge the gap later.
I would suggest everyone interested in this topic to read the electroweak current chapter of the book called "How experiments End" [3] to understand a historical example to how we approached the standard model when it was first proposed. Most of the particle physicists will not work on supersymmetry, string theory and these catchy theories that people will hear about. Most of the work is advancing and answering (and raise questions) piece by piece. Here is an example of interesting results that help us answer some questions [4]. Also I'm not saying that the field had its own problems and can improve on many aspects. I'm just against these extreme and hot takes that claims it is in a crisis or dying.
for people who posted the comment from John Carlos, I like this toot/tweet/comment by Sven Geier [5] which was what John replied.
Disclaimer: I'm a particle physicist and have a skin in the game.
[1]https://www.youtube.com/watch?v=LKiBlGDfRU8
[2] https://pdg.lbl.gov/
[3] https://press.uchicago.edu/ucp/books/book/chicago/H/bo596942...
[4] https://www.symmetrymagazine.org/article/new-results-from-th...
[5] https://mathstodon.xyz/@SvenGeier/113284011925646281
Seems like you are not downvoted on HN for rational argumentation.
I still think sabine has a point. When we consider occam's razor string theory is absurd. Just because einstein used math to show our perception of the world is flawed, doesn't mean it is likely repeatable with an overly complicated mathematical model.
Yet we live in a world, where highly decorated physicists spin a tale of consciousness beeing enabled by the collapse of the wave function (and other absurd stuff like many world interpretation). This wasted also my time, because it confused me for a while.
Let religion for the religious, philosophy to the philosopher. Physics should be a science based on observation.
My point was that sabine is claiming that the field is dying (or in a crisis). You can argue against string theory and quantum gravity research as much as you want. But this will not warrant sabine's conclusions about particle physics and why we should invest in other areas instead. She is doing this for almost a decade now.
And I don't understand your point about statistical interpretation and how it is related to being a religion. Pick up any of the mainstream interpretation and start doing calculations of lets say ground state energy of H atom and you will get the same results.
All mainstream interpretations yields the same results if calculations are done "correctly". The shut up and calculate works pretty well across interpretation because of two things you have to consider
The first thing is that all interpretations rely on four things to be able to do the calculations. ( I simplified a little bit)
1- Hilbert spaces to represent quantum states
2- Operators for observables (like momentum and energy)
3- Unitary evolution of states through the Schrödinger equation
4- Born’s rule for calculating probabilities of measurement outcomes
Thus, the underlying equations are the same regardless of interpretation.
The second thing you have to understand the role of Interpretations. They aim to explain what the mathematical structure of QM means. They differ on issues like: collapse, Is it real (Copenhagen)? just an apparent phenomenon (Many-Worlds)? or governed by additional variables (Bohmian mechanics) or the question of Determinism. Is the universe fundamentally deterministic (Bohmian mechanics)? or indeterministic (Copenhagen)?
The last thing is a really philosophical question about what exists physically—wavefunctions, particles, or multiple worlds?
These philosophical questions don’t affect the numerical predictions of quantum theory and that's part of the reason you shouldn't learn physics from science communication books.
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I think in this an other videos, what she says is "they are not even wrong" and she does have a point there.
As a non-physicist, it’s hard to understand if she has a point or not.
Any physicists care to weigh in?
Follow the links to John Baez's thoughts ("the situation is even a bit worse than she makes it sound"): https://news.ycombinator.com/item?id=41808143
Sabine is often right, but I think she's wrong here about Lorentz invariance being a problem, or at least a problem in the way she's saying.
Lorentz transformations are never going to length-contract the underlying fabric of space/spacetime. Relativistic length contractions contract moving objects, not the underlying spacetime.
In fact it's a strange and basic misunderstanding to have.
Sabine is correct. All objects in a spacetime are anchored to that spacetime, so if spacetime has a minimum length, then length contraction of moving objects has a detectable lower limit, thus violating Lorentz invariance.
She seems to be talking about spacetime itself being Lorentz contracted though.
it's true that a sufficiently fast moving object would be length contracted so much that it started interacting with the minimal LQG length, which would violate Lorentz invariance. Depending on how big the LQG loops are, that could be a fanstastically high speed that isn't achievable in the universe though.
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Depending on your reference coordinate system, space is transformed. That is the entire point of relativity theory. You might be misunderstanding things here.
Coordinates are transformed, not the actual space. Objects are length-contracted due to the electric field being length contracted.
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I agree with her views, my take on it here https://motiwala.com/blog/observations-on-the-state-of-physi...
This seems like a narrow view given that there are plenty of unanswered questions in chaos theory, etc. but physicists who think about quantum stuff typically don't like to consider the other physics Revolution of the 20th century as equivalent to theirs.
Physicist here.. I will not give Sabine more YouTube views, justifying clickbait titles. Below is just my opinion. There are certainly issues in theoretical physics. I think particularly string theory was a massive waste of effort in physics and to some degree illustration of failure of the whole system. Despite that most of other physics I would say in sensible shape, it is just harder to make progress given that we have to push to higher energies, more accurate measurements etc. The question whether there will be major advance in fundamental physics to some degree depends on new discoveries. Many people are pushing, but it is not guaranteed.
long ago i coin: scientific physics
an analogy with astrology and astronomy fits perfectly.
Remember those great men who did groundbreaking work that completely changed the fabric of society? Consensus my a, their work is self evident. If you need someone to tell you something is a great accomplishment it apparently isn't obvious.
If there is no revolution triggered by [say] relativity theory it doesn't qualify for the list of great discoveries. You need people to tell you how great it is.
funny as hell
What if String Theory is a Sophon Virus?
Then it's not really all that well made, frankly, because one of the most popular YT physicists is immune to said virus.
But - I have always dismissed cryptocurrencies thinking "people can't be that stupid". If I had not, I could have made some money. So maybe Sophons didn't expect Youtube to be a thing, either.
I'm way too late for this to be meaningful, but here's what I think! tl;dr -- gravity is the problem, we should focus on experiments and observations for a while, bring in some better mathematics, and continue the long range program of developing quantum theories that include or even produce GR.
I'm just a physics enthusiast. When I became interested in physics, I was initially a sort of partisan in the "realist" camp -- pro Einstein, anti Bohr; liked Verlinde's entropic gravity, distrusted the graviton -- but have come full circle to the opposite view. GR has massive explanatory and predictive power, and an extremely satisfying aesthetic quality, but obviously breaks down behind the curtain of a black hole's event horizon, where we cannot make observations. I say obviously because it predicts a singularity, which is just another way of saying it makes no prediction at all. On the other hand, many of my complaints about QM I now look at as unanswered questions, opportunities for inquiry. QM is based 100% on experimental observations. The theory came together in a rather ad hoc fashion at the beginning of the last century, but as it was more carefully studied theoretically and experimentally, also proved to be highly predictive, even more that GR. Yes there are big ugly, outstanding questions -- measurement collapse, the transition from microscopic quantum behavior to macroscopic classical behavior, the intractability of all but the simplest calculations -- but those are huge areas of knowledge that the future will gradually (or suddenly) fill in, as our understanding moves forward.
So, gravity, not QM, is the problem. We should start with the axioms of quantum mechanics, and look for ways to observe where QM and GR can be measured at the same time. LIGO offers opportunities like this, as the sensitivity of the instrument is well within the quantum regime. Continued study of QCD could make a testable prediction for what exists inside of a black hole. Or continue to study the very fine transitions between energy levels in the nucleus. Mathematically, maybe the Langlands program, with its rather weird, Fourier-like sums of L functions will allow us to model non-linear behavior.
And yes, string theory sort of "jumped the shark" at some point. I'm sure Ed Witten regrets saying that other pursuits were a waste of time. But the thing is, the string theory program is centered on QM, and has shown that QM can naturally produce GR, given certain unrealistic assumptions. That's mathematical progress.
I knew from the title it's gonna be Sabine Hossenfelder. Her videos are just clickbait at this point.
Is this Dang turning titles into Betteridge questions again? The original does not have a question mark.
> What's even more insane is that the only two people I can think of who have pushed back against this are Peter Woit and Eric Weinstein, and both of them are trying to sell you their own theory of everything
Sabine forgot Stephen.
https://writings.stephenwolfram.com/2021/11/the-concept-of-t...
Not exactly. She's just admitted that he isn't someone she thought of. And that's likely because she's far more aware of the contributions of physicists to this field, than the attempted contributions of non-physicists. It's not that she's not aware that they exist - in fact she's painfully aware that there are a great number of them saying all sorts of things - its that she's not individually aware of them.
That said, if she had thought of him then she would have merely increased her sample size from 2 to 3, and still had the exact same conclusion.
What absurd definition are you using that makes Stephen Wolfram not a physicist?
Wolfram is more of a physicist than most physicists.
Wikipedia:
He entered St. John's College, Oxford, at age 17 and left in 1978[17] without graduating[18][19] to attend the California Institute of Technology the following year, where he received a PhD[20] in particle physics in 1980.[21] Wolfram's thesis committee was composed of Richard Feynman, Peter Goldreich, Frank J. Sciulli and Steven Frautschi, and chaired by Richard D. Field.[21][22]
In the mid-1980s, Wolfram worked on simulations of physical processes (such as turbulent fluid flow) with cellular automata on the Connection Machine alongside Richard Feynman[29] and helped initiate the field of complex systems.[citation needed] In 1984, he was a participant in the Founding Workshops of the Santa Fe Institute, along with Nobel laureates Murray Gell-Mann, Manfred Eigen, and Philip Warren Anderson, and future laureate Frank Wilczek.[30] In 1986, he founded the Center for Complex Systems Research (CCSR) at the University of Illinois at Urbana–Champaign.[31] In 1987, he founded the journal Complex Systems.[31]
From 1992 to 2002, Wolfram worked on his controversial book A New Kind of Science,[4][33] which presents an empirical study of simple computational systems. Additionally, it argues that for fundamental reasons these types of systems, rather than traditional mathematics, are needed to model and understand complexity in nature. Wolfram's conclusion is that the universe is discrete in its nature, and runs on fundamental laws which can be described as simple programs. He predicts that a realization of this within scientific communities will have a revolutionary influence on physics, chemistry, biology, and a majority of scientific areas in general, hence the book's title
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If you want to reply to https://news.ycombinator.com/item?id=41808143 doesn't get too offtopic)
I don't like Sabine Hossenfelder's videos because they're too short. When I want to relax after work by playing a game while listening to someone drone on on youtube on a deep and esoteric subject, her videos end way too soon, and with an advertisement for her sponsor.
I just want to hear some rambling boffin expound for an hour in the background on some matter that can't possibly raise more than a few hundred views. I decided I don't like popular science videos any more. Boo.
Sean Carroll is my go to guy for long form physics and philosophy discussions that have some depth but are still accessible. His October AMA on the Mindscape podcast is over 4 hours, but I haven't listened to it yet.
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> When I want to relax after work by playing a game while listening to someone drone on on youtube on a deep and esoteric subject
Angela Collier is the answer to your plea.
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"sensational style" is one part but another is that it is hard to extract truth from Sabine's videos, at least for me, not without doing some serious research as someone with a PhD in physics.
Example starting at ~1:00 "Carlo Rovelli is fine with the theory being untestable for practical purposes. So now the situation is that either the theory is falsified or its not falsifiable..."
Is Carlo Rovelli fine with it not being testable, in that he is fine with research continuing even though it can not be tested with up coming experimental set ups? That is reasonable lots of research goes on for long periods of time with out experimental verification. From a funding point of view it makes sense to allocate more money to things that have a tighter feedback loop though. If Sabine was going to expose howe much money was going to these topics and where it could be better spent that would be worth watching.
Or is Carlo Rovelli ok with the theory being unfalsifiable in the sense that that he is ok with the research not being science? This is the straight forward meaning of Sabine's words, but are a negative attack, and one that would come off as a personal attack to many scientists I have known, one that she does not back up with anything immediately and then goes on to make more negative comments like "and Carlo complains to me because he thinks I do not understand his genius".
Ok if Sabine was going to expose Carlo Rovelli as someone who was not really practice science but was getting paid to be a scientist that would be awesome to watch and learn about. That does not happen.
"everyone who works on this just repeats arguments that they all know to be wrong to keep the money coming" - accusation of scientific fraud and defrauding the government.
Ok what percentage and total amount of founding is going to this? Is there anyone who has come forward? It would be awesome to watch something that exposed something like this. That does not happen either.
~3:19 - Arguments saying loop quantum gravity require space to be quantized, but they can not be lorentz invariant without having the quantization go to zero volume, according to Sabine, and no one has done that and extracted back out loop quantum gravity.
I am experimentalist and this is not my area. I would want to see a link to a paper/book etc. The analogy to the angular momentum operator comes off as a good place to start investigation/research but is treated dismissively, anologies like this often do not apply in the end but can still be useful.
3:53 ~ "length contraction should make that minimal area smaller than minimal proof by contradiction"
Ok that does not seem like the gottcha that it is laid out to be. Interesting stuff happens where their are apparent contradictions in physics. If experimental/observational evidence about A produces theory TA and experimental/observational evidence about B produces theory TB and they contradict each other in conditions C that is an interesting point to study look in to etc. This may not be interesting for other reasons, but the apparent contradiction does not make it obviously non interesting.
~4:27 ~ "this can't work because these deviations would inevitably so large we'd have seen them already" -
Why did Sabine talk about it being a mathematical contradiction if you can make the theory work, but it leads to physical phenomenon that we do not observe?
I can not make those two arguments jive in to a cohesive whole. Not that it can not happen, but I can not from this video and that is the conclusion, or similar, I normally reach when watching Sabine's videos and why I do not watch or recommend them generally.
I do not see any of the interesting things I mentioned above being discussed or dug into in comments so far or other new interesting takes. The issue for Sabine's videos, at least for me, is not the "sensational style".
Well, if you want a simple argument from authority, John Carlos Baez's confirmation that she's right is pretty good. If you want a better one, she very rarely gets any of her facts wrong.
Now let's go point by point.
Is Carlo Rovelli fine with it not being testable, in that he is fine with research continuing even though it can not be tested with up coming experimental set ups? He is arguing for a version of the theory that can't be tested, is continuing to do research on it, and presumably thinks that he is doing science.
If Sabine was going to expose howe much money was going to these topics and where it could be better spent that would be worth watching. Discussing how these things wind up getting funded would be a very different video. And would not likely be interesting to most of her audience.
Or is Carlo Rovelli ok with the theory being unfalsifiable in the sense that that he is ok with the research not being science? Presumably he thinks that he is doing science. Sabine's opinion clearly is that this isn't really science. However she only claims her opinion as her opinion, not established fact.
Ok what percentage and total amount of founding is going to this? Again, that would be a very different video. In 10 minutes for a general audience, you have to make decisions about what you will and will not cover. It's not a valid criticism of her that she made a choice. Particularly in a video that she disclaims as a personal rant.
Arguments saying loop quantum gravity require space to be quantized, but they can not be lorentz invariant without having the quantization go to zero volume, according to Sabine, and no one has done that and extracted back out loop quantum gravity. This is not according to her, this is according to an argument that comes from Lee Smolin. A region of space that has a specific amount of area will, according to special relativity, have a smaller area according to an observer that is traveling fast enough. By having the velocity as close as you want to C, you can make the area arbitrarily small. So your choice is to violate Lorentz invariance, or have arbitrarily small areas. If you violate Lorentz invariance, the speed for light will depend on the wavelength.
As her previous video at https://www.youtube.com/watch?v=ZlHvW6k2bcM said, this prediction of Lee Smolin has been tested to extremely high precision, and the predicted effect was not seen. That version of LQG has been falsified. The alternative supported by Carlo Rovelli is that you need to average out over quantum areas in all reference frames. This is a neat idea, but in several decades, nobody has made it work. Until someone can make it work, LQG can't produce any testable predictions.
Please note that John Baez, who worked on LQG for 10 years, specifically complimented her presentation of this particular issue. Her description of where research stands is accurate.
I am experimentalist and this is not my area. I would want to see a link to a paper/book etc. Rants generally do not come with properly cited references. That said, the previous video that this refers back to is based on https://arxiv.org/abs/2402.06009?utm_source=substack&utm_med..., which is one of the experimental tests showing that Lee Smolin's prediction is false.
The analogy to the angular momentum operator comes off as a good place to start investigation/research but is treated dismissively, anologies like this often do not apply in the end but can still be useful. It was a good place to start. After 20 years of research that has failed to turn that idea into anything workable, most people would conclude that this is an analogy that will not apply in the end. But apparently Rovelli gets mad at anyone who doubts that it will work out. One of the triggers for this rant was whatever Rovelli said to her in private. Personally, I excuse her for being human here in her reaction.
Ok that does not seem like the gottcha that it is laid out to be. Interesting stuff happens where their are apparent contradictions in physics. No, it really is the gotcha it claims to be. It's directly inside of the math. This demonstration is no different than, say, proving that sqrt(2) is irrational by proving that if you start with the smallest fraction that equals it, you can find a smaller one.
The conclusion of that gotcha is exactly what she said: if there's a minimal area then you can't have Lorentz invariance. And conversely, if you have Lorentz invariance, then you can't have a minimal area. Experimentally, we have tested for the Lorentz invariance to be expected from a minimum area based on the Planck length. It does not exist. And therefore there isn't Lorentz invariance.
Why did Sabine talk about it being a mathematical contradiction if you can make the theory work, but it leads to physical phenomenon that we do not observe? Her previous video (that triggered the nasty emails)_made this point more clearly. She's saying that there is a mathematical contradiction between having minimal areas and Lorentz invariance. This forces us to choose to have one or the other. Minimal areas leads to a testable and now falsified theory. Lorentz invariance has yet to lead to a theory that doesn't blow up with unnormalizable infinities, let alone one which can produce a testable prediction.
I can not make those two arguments jive in to a cohesive whole. Not that it can not happen, but I can not from this video and that is the conclusion, or similar, I normally reach when watching Sabine's videos and why I do not watch or recommend them generally. Is that Sabine's fault, or yours? This video is much lower quality than her normal ones. And yet absolutely none of what you think are flaws, do I think is one. Every one of your objections has an answer that jives. And the conclusion is agreed with by John Baez, whose background on this specific topic is much stronger than yours.
Perhaps, rather than looking for things to complain, you should try figuring out what she actually said. In my experience it is logically internally consistent. Even though it skewers some sacred cows.
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When I read the submission title here I immediately wondered if it was Sabine again and, well, there she was.
she said some outlandish stuff in one video - I don't remember which. I refuse to watch any more of her videos.
In other words, "she said something that completely contradicted my prejudices and the cognitive dissonance was uncomfortable, so I memory-holed what she said and immediately dismissed her claims as non-factual and avoid her from now on because I never want to experience that dissonance again".
She was ripping on the valuations and economics of quantum computing companies the other week, and her critiques were such that they could be levelled against capitalism itself and basically any company in the market. Was an obvious and clear step way out of her area of expertise.
That doesn't have anything to do with her criticism of Loop Quantum Gravity, and is precisely the derailing of the topic that dang is asking you to avoid.
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i love sabine. she's speaking the lived experience of quite a few of us who lost faith in the academy.
I like her message, but some of her recent videos have me a little worried about her. She seems on the edge of a breakdown at times.
> She seems on the edge of a breakdown at times.
Academia does this to you. She's a really well controlled case.
yeah. she does seem like she's on the edge of throwing down f-bombs, flipping tables and screaming "i'm out of here." guess it's to her credit she hasn't done that.
I've said this before in not the same words, and I am always downvoted here on hackernews: people need to understand theory of knowledge before they understand science. Physics and physicists are the worst offenders.
This strongly depends on what you mean by "theory of knowledge".
If you mean the practical importance of self-honesty, and a historical awareness of how easily we slip into self-delusion, then I agree. See, for instance, https://calteches.library.caltech.edu/51/2/CargoCult.htm for a very famous speech on exactly this topic. A lot of Feynman's writing touches on the same issue.
If you mean the musings of philosophers on epistemology, then I emphatically disagree. The philosophers in question generally have failed to demonstrate that they understand science. And when they venture into science, they generally fail to live up to the ideals that they proclaim that scientists should follow. As an example I direct you to the sight of Karl Popper arguing to the end of his days that quantum mechanics cannot be a correct scientific theory. An opinion that began because a probabilistic theory cannot in principle be falsified.
In fact QM is a scientific theory, and it stands as an example falsifying Popper's criterion for science!
I find it very ironic that Feynman is so disliked by philosophers for having been honest about how irrelevant they are to science. And philosophers in turn have failed to recognize Feynman's explanations of how to do science as a key topic that should be included in any proper philosophy of science.
I meant your second perspective.
I'm in the Popper camp on your example. You may have good reasons as to why you say he's wrong, but isn't that the scientific method: showing things to be false. If it can't be shown to be false then how can it be scientific? It might be some other branch of thought.
On the specific case of quantum mechanics - I want to see these forever promised quantum computers actually doing something useful. The promises went from (Vs classical computers) they will do everything faster, to they will do some things faster, to they will do some things not achievable at all. And yet, they still haven't done anything as far as I can tell. Physicists need to answer honestly for this.
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If by "theory of knowledge", you mean they need to have read a bunch of philosophical musings on epistemology, then I strongly agree with the downvoters, because that's utter nonsense. If you mean anything else by that, then you're being way too vague to contribute to a technical discussion, so again I agree with the downvoters. Try defining what you mean by "theory of knowledge" and explain why you think that's required to "understand science" (and you might want to explain what you mean by that too) and I suspect you'll see a lot fewer downvotes.
Theory of knowledge "is a branch of philosophy that examines the nature, origin, and limits of knowledge". Scientists need to understand the limits of knowledge which may be acquired by science.
Scientists think they are in the unique possession of tools which ascertain truths - this is misled.
Amusingly, the International Baccalaureate Diploma Programma - an A-Levels like uni-prep course - has a subject called TOK: Theory of Knowledge with these intentions.
And it was with people of this very course that I have been impressed by. They learnt things at a young age and it stayed with them.
I have a pet conspiracy theory for why there has been so little progress in physics for so long. The invention of the nuclear bomb scared a lot of people, it made them scared of physics. What else might physicists turn up that could change the world in dramatic ways? Anti-gravity? Ray guns? Other dimensions? Travel to other worlds? All bad for business, no one is going to buy your airplanes or air craft carriers if they can buy an anti-gravity machine. So physics was suppressed by both business and government. Physicists were given "safe" work to do (ITER, quants) that would occupy them and keep them from exploring wild stuff. Grant financing was controlled so that only safe research would be conducted. It would be fairly invisible to the world, just a few high level decisions would determine how the funding was directed. I get the impression that if this was indeed a conscious decision that it's starting to fall apart as younger generations take over and become frustrated with the direction of physics. They weren't there when the A-bomb was invented, and nuclear weapons have not been on peoples minds much for a long time, most people have not lived in a time when one was used. So they see interesting topics and want to explore them and encounter resistance from more established scientists. It's a conspiracy theory because it would involve some buy-in from a fair number of physicists to make it work, but a lot of physicists when I was getting my BA in physics were very loudly saying "never again" about atomic weapons and felt it had tarnished the whole profession. It's very difficult to say what humanity would be capable of handling in terms of radical new inventions. Anti-gravity could solve many large problems, but it might make it even easier to destroy Earth. Once new knowledge exists it is hard to suppress it. Stopping it from from ever existing seems easier. I guess we'll find out if physics has been suppressed if the dam breaks and new ideas start proliferating. The nature of the new physics would be a big clue as to whether research in it was suppressed. I'm reminded of Elon Musk, he seems to have had really radical success in some very stagnant industries, just by trying instead of accepting limits, and being able to fund his ideas himself.
The theory stops working imho if you take competition into account. The world is not aligned as a single bloc of power. While it’s not completely unthinkable (but extremely unlikely, imho) that some scientists plus some decision makers from, say, the liberal west might collude to achieve this kind of suppression, their counterparts from one or multiple other blocs might not, because they want to dominate and anti-gravity guns surely give you some nice advantage.
You'd be amazed how quickly powerful discoveries find military purpose.
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The desire to dominate can take a weird turn if using your anti-gravity guns reveals them and makes it likely others will soon invent the same. There is precedent for this, say in electronic warfare or cyberwarfare. As soon as you reveal your uber virus, anyone can take it apart and modify it for their own purposes. So you don't reveal it except as a last resort. Competition doesn't come into play then, everyone hides their secret weapons and never uses them unless they have to, and tries to make sure information in that area is suppressed. However, as I say in other comments, this may have been a bottom up conspiracy, not a top down conspiracy, though it may have moved to the top as the scientists themselves gained power. But the fear would still exist at all levels; sure your anti-gravity gun gives you an advantage, but what if it eventually causes random micro black holes to appear near where you use it, obliterating infrastructure before evaporating? We just don't know what the repercussions of new technologies will be, and while the risks have seemed low in areas like software, the risks seem higher with fundamental new physics. People are historically pretty bad at predicting how technology/science will play out in the long term. AI was a joke for a long time, until it wasn't. The internet was hailed as revolutionary, but it seems very different than it did in the year 2000. It's a lot like computer security, you can imagine the possibilities, but you probably can't imagine ALL the possibilities. It takes time and collaboration to scope out what it is that is new that can now be accomplished. That uncertainty scares some people and excites others. Seems kind of like walking through a minefield littered with Christmas presents. Some people might decide to leave the presents where they are.
There are some good comments here, thanks! There has been an international component to physics research cooperation. It seems not inconceivable that physicists in many countries, meeting at paper conventions and such might have agreed and recruited each other to try to prevent the next atomic bomb type invention. So while competition between countries is certainly real, competition between scientists might be somewhat different. You'd think there would be some people who would pursue it regardless, but they'd probably have to work with a team, and not everyone on the team may have supported the goals. It's just a theory, but it has some plausibility. Perhaps there are people everywhere who have decided not to be part of endeavors that could be disruptive and they've done us all a favor or have kept us from discovering the secrets of the universe. Who knows? The ethics of science has been mostly left to chance and individual decisions.
An easier theory is that the Standard Model is so good that it's very difficult to find anywhere it fails. So there's no experimental fuel to propel physics forward.
https://en.wikipedia.org/wiki/List_of_unsolved_problems_in_p...
What time frame are you talking about here? Starting in 01950, 01995, 02010?
If we're talking about 01995, it's conceivable that, say, the US and CERN could coordinate to suppress research into hafnium bombs, AVLIS, antigravity, or whatever. If we're talking about research much prior to that point, though, you'd have to include the Russians in the conspiracy. Probably not just any Russians, either; probably Khrushchev, Brezhnev, Andropov, Tsar-Bomba-era Sakharov, and his successors. And, on the other side, people like J. Edgar Hoover, JFK, McNamara, Kissinger, Johnny von Neumann, and Teller.
I don't want to say it's literally impossible for Brezhnev or his underlings to have made a secret agreement with Kissinger and Teller to suppress the development of theoretical physics in order to keep the world predictable. But I do think it's pretty implausible, and there would have been an enormous incentive to cheat on any such secret agreement.
In the 01990s, though, it could have become plausible. But, remember that that's also when Pakistan became a nuclear weapons state, shortly followed by North Korea in 02006. And the People's Republic of China has had nuclear weapons since 01964, so they evidently had significant physics capabilities that they were willing to use for warfare (which was a huge priority; Mao reorganized the country's economy to resist an anticipated US invasion), and they dominated the TOP500 supercomputer list until this year, when they withdrew from it in apparent protest against the efforts of the USA to reverse their technological progress with a worldwide system of export controls.
So I think there's maybe a ten-year window when this could have happened somewhat, about 01992 to 02002. Both before and after that, there are too many countries with strong physics communities that are too bitterly opposed to make such cooperation plausible.
I have never seen someone prefix dates with a zero like this. Why are you doing that?
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Reading the comments here my thinking has been revised. I'm no longer suggesting the elites were conspiring, at least initially, I'm suggesting the physicists were conspiring for ethical reasons. Some of them may have moved up the ladder and reached positions of some power. Physics is magic to most people, hiding possibilities in math and technicality seems possible. Anyone who has written code professionally has probably been faced with similar decisions, biases can be encoded, and you have to decide how you are going to approach these things. For example, do you add a race field to the medical database or not? In 1990 it was often left up to the programmer. Sometimes things are decided far below the level of the people running the show. Regardless, I do think my theory is far fetched, innate curiosity seems likely to have caused some people to explore further regardless of the risks, and an overt conspiracy that eventually reached high levels seems likely to have been soon discovered.
Perhaps this is of interest to you.
https://m.youtube.com/watch?v=yTiztUNrhhM
I'd heard the name LaRouche but I've never read his history:
https://en.wikipedia.org/wiki/Lyndon_LaRouche
Quite astounding, he seems to have been both woke in some ways (climate change) and fundamentally misguided. I can see a lot of Trump's playbook in his life. I was imagining a much more passive conspiracy, people refusing to participate for ethical reasons, rather than an elite conspiracy by the Venutians/Illuminati. The video seems unintelligable, he makes so many references to obscure history that may or may not be true (and how would he know?) it becomes meaningless without years of research and even then, the intentions and thoughts of historical figures are difficult to ascertain.
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Some secrets keep themselves.
> "The universe is full of magical things patiently waiting for our wits to grow sharper." —EP
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Theoretical physics are theoretical; that seems to be the crux of her problem. And in that light it makes sense that she's become an influencer who makes content instead of someone who devotes most of their time to advancing the science. Yes, oftentimes people will be paid to work on problems, and they'll end up in a cul-de-sac. That will be the case for the majority of the field in the case of something like quantum physics. But if we pay enough of these people to sit in rooms and work on problems, maybe one of them will figure something out. That's how science progresses.
> enough of these people
There’s more than enough already. (And, historically, you only need less than a dozen.)
> (And, historically, you only need less than a dozen.)
This seems initially like a pretty outlandish claim to me. Could you clarify what you're referring to here?
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[flagged]
"Please don't post shallow dismissals, especially of other people's work. A good critical comment teaches us something."
"Please respond to the strongest plausible interpretation of what someone says, not a weaker one that's easier to criticize. Assume good faith."
https://news.ycombinator.com/newsguidelines.html
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I think that you have half a point. You're absolutely right that just because people are paid to think about things, doesn't mean that they are making progress. And there is a lot of evidence that this is true today in the foundations of physics.
However string theory was not intentionally untestable. In https://www.youtube.com/watch?v=eRzQDyw5C3M she gives a good history of why it was originally invented, what testable predictions it made, how it failed those tests. And then how string theorists who were trying to find relevance for their work tried to keep it going as it stumbled into being untestable.
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This is a very cruel reading of string theory. Intentional? What?
Exactly. Consistently untestable and unfalsifiable claims for decades has to be seriously questioned at some point, and I think we're well beyond that point. This is especially true for string theory. I'm particularly fond of how Angela Collier laid out the timeline of string theory in her video on it[0] as well as the consequences that science communication is now facing as a result.
[0] = https://www.youtube.com/watch?v=kya_LXa_y1E
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There is no evidence to suggest that string theorists designed the theory to be untestable.
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How is it "intentionally untestable"? I get that it is practically untestable, but as far as I know, there are people working to try to find some possible tests.