Why the weak nuclear force is short range
profmattstrassler.com
profmattstrassler.com
Previously, we had statement "the weak force is short range". In order to explain it, we had to invent a new concept "stiffness" that is treated as a primitive and not explained in terms of other easy primitives, and then we get to "accurately" say that the weak force is short due to stiffness.
I grant the OP that stiffness might be hard to explain, but then why not just say "the weak force is short range -- and just take that as an axiom for now".
It seems to me like the right criteria for a good model is:
* there are as few non-intuitable inferences as possible, so most conclusions can be derived from a small amount of knowledge
* and of course, inferences you make with your intuition should not be wrong
(I suppose any time you approximate a model with a simpler one---such as the underlying math with a series of atomic notions, as in this case---you have done some simplification and now you might make wrong inferences. But a lot of the wrongness can be "controlled" with just a few more atoms. For instance "you can divide two numbers, unless the denominator is zero" is such a control: division is intuitive, but there's one special case, so you memorize the general rule plus the case, and that's still a good foundation for doing inference with)
Unfortunately the version of QM that is taught in textbooks is not especially useful for figuring out what the intuition is. I have my own model that I've concocted that does a much better job, but there are still plenty of things I don't understand well (having not done, like, a graduate degree in it).
What I learned over the years is that, unfortunately, at some point you rely on maths. You solve equations, make predictions, and compare this to measurements. Uf they match your model (conveyed through equations) is "good for now"
The problem is that a lot of what you mathematically witness, then measure at macro scales (you do not get to measure quantum effects at their scale, only their effects on the apparatus) does not make sense at our scale.
A particle appearing for a shirt moment from nothing, interacting with another particle and vanishing, WTF?
A particle with energy X hitting a "wall" with energy Y > X and going through? WTF?
Single particles interacting with each other? Another WTF
QM is full of surprises that sound cool when presented with enthusiasm and simple words, or used in MARVEL movies but they are as intuitive for typical people as cosmic travel for Neanderthals . Sure you can handwave your way through them but how does that work with a cave and wall paintings - which is what they would witness on an everyday basis.
Things like: if you think of particles as blobs of mass and charge, you get the wrong answers; if you think of them as interfering waves then you start to get right answers. If you think of them as interfering light waves, you get the right answer for a while until you hit a situation where spin=1 gives the wrong answer, or m≠0 means the transverse component is nonzero, so you fix your intuition on that and get better answers. If you think of particle-waves as discrete atomic objects you can't intuit how different particles can be created in scattering; if you think of them as a label given to a particular vector which can be decomposed as a sum of other vectors which interact differently with different fields then you can see how particle creation/annihilation works.
Etc. There certainly are models you can construct in your mind that make this stuff start to make sense. I don't have them all, but I'm working on it. Mindlessly doing math might work for homework problems but it's not enough for actually explaining anything; you need some mental picture of what's going on as well. But the math is always there to make your intuitions concrete and keep them grounded in reality.
I do not know your theory so I cannot comment on it, but when I was in academia I received quite a lot of these theories and they were breaking down rather quickly.
Physicists are always interested in new things but what you present must make sense and - most importantly - explain things and agree with measurements. If suddenly you end up with incorrect values it means the model is wrong. It may be completely wrong or maybe it needs adjustments.
The best way to send your message to the world is to publish.
Also, the math section demonstrated how stiffness produces both the short-range effect and the massive particles, so instead of just handwaving "massive particles is somehow related to the short range" the stiffness provides a clear answer as to why that's the case.
You might also ask where that term comes from. It really is "axiomatic": there is no a priori explanation for why anything like that should be in the equations. They just work out if you do that. Finding a good explanation for why things have to be this way and not that way is nothing more and nothing less than the search for the infamous Theory of Everything.
When I was a physics undergrad, most of my professors were fans of the "shut up and calculate" interpretation of quantum mechanics.
Ultimately, this is probably just a symptom of still not having yet discovered some really important stuff.
Spiritually it feels more like what happened later, when people took the idea of quantized energy seriously and began finding ways to make it a theoretically consistent theory which also required a radical new approach of disregarding old intuitive assumptions about the way the most fundamental things worked solely to obey a new abstract, esoteric, purely theoretical framework (an approach which was sometimes controversial especially with experimentalists).
But of course this new theory of quantum mechanics turned out to be immensely successful in totally unprecedented ways, in a manner similar to Relativity and it's "theory first" origin with trying to ensure mathematical consistency of Maxwell's equations and disregarding anything else in the way (and eventually with Einstein's decade long quest to find a totally covariant general theory that folded gravity into the mix).
With physics the more I dug into "why" it was rarely the case that it was "just because", the justification was nearly always some abstract piece of math that I wasn't equipped to understand at the time but was richly rewarded later on when I spent the time studying in order to finally appreciate it.
The first time I solved Schrodinger Equation for a hydrogen atom, I couldn't see why anyone could've bothered to try discovering how to untangle such a mess of a differential equation with a thousand stubborn terms and strange substitutions (ylm??) and spherical coordinate transformations - all for a solution I had zero intuition or interest in. After I had a better grasp of the duality between those square integrable complex functions and abstract vector spaces I found classical QM elegant in an way I wasn't able to see before. When basic Lie theory and representations was drilled into my head and I had answered a hundred questions about different matrix representations of the SU(n) and S0(3) groups and their algebras and how they were related, it finally clicked how naturally those ylm angular momentum things I saw before actually arose. It was spooky how group theory had manifested in something as ubiquitous and tangible as the structure of the periodic table. After drudging through the derivation of QFT for the first time, when I finally understood what was meant by "all particles and fields that exist are nothing more than representations of the Poincare-Spacetime Algebra", I felt like Neo when everything turned into strings of code. And there's no point describing what it was like when Einstein's field equations clicked, before then I never really got what people meant by the beauty of mathematics or physics.
I guess its not really the answer "why" things are, but the way our current theories basically constrain nearly everything we see (at least from the bottom up) from a handful of axioms and cherry-picked coupling constants, the rest warped into shape and set in stone only by the self-consistency of mathematics, I feel like that's more of a "why" than I would've ever assumed answerable, and maybe more of one than I deserve.
In a sense, I think your explanation is consistent with mine, but with the deeper context of math being a language itself, and the math itself being a more satisfactory explanation to someone with a greater intuition for what the equations actually mean. I can pump through all of the major equations in physics and explain almost anything I want with them, but it always just feels like rote application of algebra rules to completely arbitrary seeming formulas- nothing like what you describe. Frankly, I think I was more interested in girls than studying when I was a physics student decades ago, and I could probably get a lot more out of it revisiting this stuff now.
However, I do still think there is a real chance that we are missing something big that would fit all of these pieces together with qualitative explanations. Personally, I think Julian Barbour is likely on the right path with his timeless physics, but if so it will need a lot more research and development.
Well, you build "intuition" via "experience"--generally lots of experience to get small amounts of intuition.
> Usually the qualitative descriptions don't quite make sense if you think very hard about them- and if you dig deeper it's often just "we found some math that fits our experimental data"
Well, the math needs to fit the data and have predictive power. That "predictive" side is really important and is what sets "science" apart from everything else.
> Ultimately, this is probably just a symptom of still not having yet discovered some really important stuff.
Sure. But wouldn't the world be incredibly boring if we had it all figured out?
There are limits to how much you can do though, I mean at some point it's going to be "just math that fits reality". If you try to enumerate the number of mechanisms and realities that could give a decent enough diversity of composition that life can arise in some form, there's going to be more than our universe possible.
Imagine my surprise!!
We might live in a simulation!
You don't just "find some math that fits the data" the way you would mechanically tune the parameters of a given mathematical model to fit empirical data.
Indeed finding a mathematical formulation that seems to describe a corner of reality with any fidelity is such an extraordinary thing that physicists have always puzzled about why it is even possible!
Now it turns out that these mathematical inventions "work" even when our intuition (built on experiences around human scale) cannot quite grasp them. This is the case both in the realms of the very small (quantum) and very big (relativity).
This doesnt mean that at some point we might not find deeper mathematical abstractions that "work better" (e.g., this was the string theory ambition) but the practical result would still be every bit "shut up and calculate".
If you need to assume some axiomatic concept it's better to assume one that can used to derive a lot of what is observed.
But electric charges cancel out each other over big regions, while gravity never cancels.
So say you have a spring if you compress it, it pushes because it wants to go back to its natural length and likewise if you stretch it there is a restorative force in the opposite direction. The constant of proportionality of that force (in N/m) is the stiffness of the spring, and the force from the spring[1] is something like F=-k x with x being the position measured from the natural length of the spring and k being the stiffness. So not knowing anything about electromagnetism I read this and thought about fields having a similar property like when you have two magnets and you push like poles towards each other, the magnetic field creates a restorative force pushing them apart and the constant is presumably the stiffness of the field.
But obviously I’m missing a piece somewhere because as you can see the force of a spring is proportional to distance whereas here we’re talking about something which is short-range compared to gravity and gravity falls off with the square of distance so it has to decay more rapidly than that.
Edit to add: in TFA, the author defines stiffness as follows:
For a field, what I mean by “stiffness” is crudely this: if a field is stiff, then making its value non-zero requires more energy than if the field is not stiff.
[1] Hooke’s law says the force is actually H = k (x-l)ŝ where k is stiffness, l is the natural length of the spring and ŝ is a unit vector that points from the end you’re talking about back towards the centre of the spring.
Electrons are tiny and nuclei are huge, so you have a bunch of mobile charge carriers which cost energy to displace to an equilibrium position away from their immobile "homes". A collection of test charges moving "slowly" through the plasma (not inducing B field, electrons have time to reach equilibrium positions) will produce exponentially decaying potentials like in the article. If you want to read more, this concept is called "Debye Screening"
Anyway, this might be a more helpful approach than trying to imagine a spring - a "stiff" field equation is an equation for a field in a medium that polarizes to oppose it, and you can think of space as polarizing to oppose the existence of a Z Boson in a way that it doesn't polarize to oppose the existence of a photon.
Perhaps an approach trying to actually explain the Feynman propagators would be more helpful? Either way, I agree that if someone wanted to understand this all properly it requires a university education + years of postgrad exposure to the delights of QED / electroweak theory. If anyone here wants a relatively understandable deep dive, my favourite books are Quantum Field Theory for the Gifted Amateur [aka graduate student] by Stephen Blundell [who taught me] and Tom Lancester [his former graduate student], and also Quarks and Leptons by Halzel and Martin. It is not a short road.
> ...causing a growing rift between scientists and the normal population.
True.
Now, to my 'craft' (GRC). I lately catch myself speaking like Peter Thiel, taking 20-30 second 'silences', build in my mind what I want to say, 'translate it' to simple(r) English, and then slowly say it out loud to make sure I pave the path with mental & verbal stepping stones without using any jargon.
I very well understand what I want to say, but the gap between in the knowledge and the use of language puts the onus to the explainer.
Ie: “I can’t explain it in terms of something else you’re more familiar with because I don’t understand it terms of anything else you’re more familiar with.”
How so? It's the standard equation for a scalar (spin zero) field.
EDIT: yes I tried pasting it in to Gemini, 4o, and Claude. Only Claude was able to zero-shot create the latex and an html wrapper that renders it, and open the html preview on iOS. It worked great.
Roughly put:
- A particle is a "minimum stretching" of a field.
- The "stiffness" corresponds to the energy-per-stretch-amount of the field (analogous to the stiffness of a spring).
- So the particle's mass = (minimum stretch "distance") * stiffness ~ stiffness
The author's point is that you don't need to invoke virtual particles or any quantum weirdness to make this work. All you need is the notion of stiffness, and the mass of the associated particle and the limited range of the force both drop out of the math for the same reasons.
Then why not just call it "mass"? That's what it is. How is the notion of "stiffness" any better than the notion of "mass"? The author never explains this that I can see.
I think stiffness is an ok term if your aim is to maintain a field centric mode of thinking. Mass as a term is particle-centric.
It seems these minimum-stretching could also be thought of as a “wrinkle”. It’s a permanent deformation of the field itself that we give the name to, and thus “instantiate” the particle.
Eye opening.
"Stiffness" to me isn't a field term or a particle term; it's a condensed matter term. In other words, it's a name for a property of substances that is not fundamental; it's emergent from other underlying physics, which for convenience we don't always want to delve into in detail, so we package it all up into an emergent number and call it "stiffness".
On this view, "stiffness" is a worse term than "mass", which does have a fundamental meaning (see below).
> Mass as a term is particle-centric.
Not to a quantum field theorist. :-) "Mass" is a field term in that context; you will see explicit references to "massless fields" and "massive fields" all over the literature.
Mass is a bad term because it's loaded with so many meanings and equivalences already. But also in the kindest and most accurate reading here it still doesn't naturally lead to explaining why some forces have limited range the way that term "stiffness" does, which was the whole point of the article.
No, because no physicist tries to argue that "color" is an appropriate term because of some physical interpretation that involves actual physical properties of colored objects.
This author, OTOH, appears to be arguing that "stiffness" is a better term than "mass" because of some physical interpretation that involves actual physical properties of stiff objects. An analogy with quarks would be to argue that "color charge" is an appropriate term because red, green, and blue quarks somehow have actual properties associated with those colors.
> it still doesn't naturally lead to explaining why some forces have limited range the way that term "stiffness" does
I'm not sure the explanation of that in terms of "stiffness" is any better, because in the setting where the term "stiffness" comes from, there is no such thing as what this author calls a "floppy" object. So his explanation only "explains" the behavior of forces associated with massive gauge bosons at the price of throwing away an explanation of the behavior of forces associated with massless gauge bosons.
They do, there are 3 and they add up like primary colors, so all 3 make stuff colorless. That's why those names were chosen. Because of similarities with color we know from color theory.
> there is no such thing as what this author calls a "floppy" object
It's easy enough to imagine as an unattached rope so pulling at one spot affects the whole rope because nothing holds remote parts of the rope in place. The only way for a wrinkle to exist in such rope is to travel at "rope speed". If there's stiffness then a wrinkle can travel at any speed or none at all, because it can oscilate without moving, which is rest energy (mass). So it explains all bosons.
What's great with this analogy is that it coveys that both mass and force range arise from a single term of the equation. There's really no causal connection between them. Neither limited range causes mass nor mass causes limited range. They both come from a single intrinsic field "quality".
There's also no anti-blue color in color theory but it's easy to imagine it so you can intuitively understand its behavior.
Not instantly; the force you apply at one point still has to be transmitted through the rope. And if the rope is unattached and not taut, it won't transmit force well at all, and you have very limited control over how the rest of the rope will move when you pull on one part.
I don't see how any of this is a useful analogy to how massless gauge bosons work in forces like electromagnetism.
That's fine. No analogy works for everybody.
In the unit analysis that is most natural to quantum field theory, it's mass.
For this discussion it makes sense call the "mass" of a field "stiffness" instead, since it's not known a priori that it corresponds to particle mass.
Here the "stiffness" is interpreted as the effect of nearby charges "screening" a perturbing "bare" charge of the opposite sign. If you solve the equation you find the that effective electric field produced by the bare charge is like that of the usual point charge but with a factor exp(-r/λ). So, the effect of the "stiffness" term is reducing the range of the electric interactions to λ, which is called the Debye length. see this illustration [1].
Interestingly, if you look at EM waves propagating in this kind of system, you find some satifying the dispersion relation ω² = k²c² + ω_p² [2]. With the usual interpretation E=ℏω, p=ℏk you get E² = (pc)² + (mc²)², so in a sense the screening is resulting in "photons" gaining a mass.
[1]: https://en.wikipedia.org/wiki/File:Debye_screening.svg
[2]: https://en.wikipedia.org/wiki/Electromagnetic_electron_wave#...
The nuance is this: Naturally, in a field theory the word "particle" is ill-defined, thus the only true statement one can make is that: the propagator/green function of the field contains poles at +-m, which sort of hints at what he means by stiffness.
As a result of this pole, any perturbations of the field have an exponential decaying effect. But the pole is the mass, by definition.
The real interesting question is why Z and W bosons are massive, which have to do with the higgs mechanism. I.e., prior to symmetry breaking the fields are massless, but by interacting with the Higgs, the vacuum expectation value of the two point function of the field changes, thus granting it a mass.
In sum, whoever wrote this is a bit confused and just doesn't have a lot of exposure to QFT
But I don't particularly like the whole "mass vs not mass" discussion as it's pointless
Recognizing correct analogies is not easy and it's insanely powerful educational tool.
Incredible.
https://scholar.google.com/citations?user=19WGkFsAAAAJ&hl=en
be sure to check past the first 20 papers or so, like, oh, say his 1990 paper with Michael Peskin (438 citations), a copy of which can be found at <https://www.slac.stanford.edu/pubs/slacpubs/5250/slac-pub-53...>.
It does have a name: mass!
What I'm skeptical of is that this "stiffness" is somehow logically or conceptually prior to mass. Looking at the math, it just is mass. The term in the equation that this author calls the "stiffness" term is usually just called the "mass" term.
If you are referring to the claim in the article that goes along with the equation E = m c^2, that claim is the author's personal interpretation, which I don't buy. The mass appears in the dispersion relation whether the particle is at rest or not. "Rest mass" is an outdated term for it; a better term is "invariant mass", i.e., it's the invariant associated with the particle's 4-momentum. Or, in field terms, it's the invariant associated with the dispersion relation of the field and the waves it generates.
At the same time, the author does not give any different definition; he says it's "stiffness". In the comment, he writes:
> The use of a notion of “stiffness” as a way to describe what’s going on is indeed my personal invention. Physicists usually just call the (S^2 phi) part of the equation a “mass term.” But that’s jargon, since this thing doesn’t give mass to the field; it just gives mass to its particles, which exist only in the context of quantum physics. The word “mass term” also doesn’t explain what’s going on physically. My view is that “stiffness” conveys the basic physical sense of what is happening to the field, an effect it has even without accounting for quantum physics.
So well, it is mass. Maybe not mass one may think about (in physics, especially Quantum Field Theory, there are a few notions of mass, which are not the same as what we set on a scale), but I feel the author is overzealous about not calling it "mass (term)".
So, I am not convinced unless the author shows a way to have massive particles carrying a long-term interaction (AFAIK, not possible) or massless particles giving rise to short-term interactions (here, I don't know QFT enough so that it might be possible). But the burden of proof is on the inventor of the new term.
Turning Waves Into Particles https://www.youtube.com/watch?v=tMP5Pbx8I4s
And if unfamiliar, that channel constantly delivers high quality thought provoking content on the nature of light.
Very enjoyable and thought provoking stuff though!
Edit: spelling
The problem is it's upfront that "X thing you learned is wrong" but is then freely introducing a lot of new ideas without grounding why they should be accepted - i.e. from sitting here knowing a little physics, what's the intuition which gets us to field "stiffness"? Stiff fields limit range, okay, but...why do we think those exist?
The article just ends the explanation section and jumps to the maths, but fails to give any indication at all as to why field stiffness is a sensible idea to accept? Where does it come from? Why are non-stiff fields just travelling around a "c", except that we observe "c" to be the speed of light that they travel around?
When we teach people about quantum mechanics and the uncertainty principle even at a pop-sci level, we do do it by pointing to the actual experiments which build the base of evidence, and the logical conflicts which necessitate deeper theory (i.e. you can take that idea, and build a predictive model which works and here's where they did that experiment).
This just...gives no sense at all as to what this stiffness parameter actually is, why it turned up, or why there's what feels like a very coincidental overlap with the Uncertainty principle (i.e. is that intuition wrong because actually the math doesn't work out, is this just a different way of looking at it and there's no absolute source of truth or origin, what's happening?)
However, it is actually a similar approach to how De Broglie, Schrodinger, and others originally came up with their equations for quantum behavior - we start with special relativity and consider how a wave _must_ behave if its properties are going to be frame-independent, and follow the math from there. That part is equation (*), and the article leads with a bit of an analogy of how we might build a fully classical implemenation of it in an experiment (strings, possibly attached to a stiff rubber sheet) so we get some everyday intuition into the equation's behavior. So from my point of view, I found it very interesting.
(What the article doesn't really get into is why certain fields might have S=0 and others not, what the intuition for the cause of that is, etc. It also presupposes you have bought into quantum field theory in the first place, and wish to consider the fundamental "wavicles" that would emerge from certain field equations, and that you aren't looking closely at the EM force or spin or any other number of things normally encountered before learning about the weak force).
I can't point at any outright mistakes, but for example I think the dismissal of the common interpretation of virtual particles in Feynman diagrams is not persuasive. If you think the prevailing view among experts is wrong then the burden of proof is high, perhaps right than you can reach in am article pitched so low, but I don't feel like reading his book.
What's more distressing than the insular knowledge cults of modern physics is the bizarre fixation on unfalsifiable philosophical interpretation.
That just makes it incomprehensible to outsiders when they quibble over the metaphors used to explain the equations that are used to guess what may happen experimentally. (Rather than admitting that any definition is an abstraction and any analogies or metaphors are merely pedagogical tools.)
My kneejerk reaction: Give me the equations. If they are too complicated give me a computer simulation that runs the equations. Now tell me what your experiment is and show me how to plug the numbers so that I may validate the theory.
If I wanted to have people wage war over my mind concerning what I should believe without evidence, I would turn back to religion rather than science.
Anyway, I hope this situation improves in the future. Maybe some virtual particle will appear that better mediates this field (physics).
If I write a partial differential equation that I came up with randomly and ask you to find all the potential solutions that really doesn't tell you anything about the natural world.
The Lagrangian is just "conservation of energy" (L = T[kinetic] - V[potential]). There isn't some magic, it's a statement that the energy needs to go somewhere.
Your straw-man belies the underlying issue you are experiencing, you don't just come up with a PDE, you see nature and then you describe ways to conserve counts of things, "energy", "population", whatever. The PDEs describe the exchange between these counts. The accuracy and additional terms are about more accurately representing the counts and conservation of things.
Math is all you've got to work with, we wouldn't have modern day physics without math.
The issue is that people think they can find some kind of magic shortcut by playing around with abstractions without reference to or grounding in physical observables. That's not a math problem, that's a psychology problem.
Once again, my point is that people are trying to take shortcuts with abstractions that are not grounded in reality. That is a matter of self-discipline, of priorities, of putting the cart before the horse. Consider string theories: we have worked out so many ways in which strings can behave, etc. with so many possibilities and permutations. However, we never proved the ground reality for strings, we just ran with a bunch of assumptions and then parameterized them, went meta a bunch of times, and called that a research program.
All of that mathematical sophistication and model-building could have went to, e.g. perfecting QCD, or even in other directions.
The grounding is 3 years of advanced math.
Because not everyone has the prerequisite math or time/attention to go into quantum field theory for a rather intuitive point about mass and fields.
This reminds me a bit of how high school physics classes are sometimes taught when it comes to thermodynamics and optics. You learn these "formulas" and properties (like harmonics or ideal gas law) because deriving where they come from require 2-3 years of actual undergraduate physics with additional lessons in differential equations and analysis.
This gets into the problem though: the article is framed as "the Heisenberg explanation is wrong". Okay...then if thats your goal, to explain that without math, you need to do better then "actually it's this other parameter, trust me bro".
As read, I cannot tell if there's something new or different here, or if "stiffness" just wraps up the Heisenberg uncertainty principle neatly so you can approach the problem classically.
The core question coming into the article which I was looking for an answer for is "is the Heisenberg uncertainty principle explanation wrong?" and...it doesn't answer that. Showing that you can model the system a different way without reference to it, but by just introducing a parameter which neatly gives the right result, doesn't grant any additional explanatory power. It's just another opaque parameter: so, is "stiffness" wrapping up a quantum truth in a way which interacts with the real world? Is the uncertainty principle explanation unable to actually model these fields at all? I have no idea!
But the Uncertainty principle is something you can demonstrate in a first year lab with a laser and a diffraction grating, and turns up all the time in all sorts of basic physics (i.e. tunneling). Where does "stiffness" turn up and how does it relate? Again, I have no idea! The article purports to explain, but rather just declares.
https://profmattstrassler.com/2025/01/10/no-the-short-range-...
> quantum physics plays no role in why the weak nuclear force is weak and short-range. (It plays a big role in why the strong nuclear force is strong and short-range, but that’s a tale for another day.)
Could a competent software engineer, even without knowing the fundamental origins of things like particle masses or the fine-structure constant, capture all known fundamental interactions in code?
I guess I'm trying to figure out the complexity of the task of universe creation, assuming the necessary computational power exists. For example, could it be a computer science high school project for the folks in the parent universe (simulation hypothesis). I know that's a tough question :)
Most people in the field don't think his research will be fruitful, but that doesn't make him a crack pot
Wolfram's claim is that Cellukar Automata can provide as good or better mathematical model of the universe than current current theories, by commonly appreciated metrics such as "pasimony of theory" (Occam's Razor). He's not making claims about metaphysical truth.
He also did some important early work on cellular automata if iirc.
Then he wrote "A New Kind of Science", which reads like an ego trip and was not received well by the community (it is a massive tome that could have been summarized with a much smaller book). He also tried to claim discoveries from one of his workers due to some NDA shenanigans (or something along these lines iirc). The latter doesn't make him a crank, just a massive egotist, which is a trait nearly all cranks have. Sabine Hossenfelder did a video on him and how he only publishes in his own made up journals and generally doesn't use the process used by all other scientists. I think a lot believe where there is smoke, there is fire. To his credit, she also mentioned that some physicists gave him some critical feedback and he did then go and spend a bunch of time addressing the flaws they found.
>There’s a whole way of thinking about the world using the idea of computation. And it’s very powerful, and fundamental. Maybe even more fundamental than physics can ever be.
>Yes, there is undecidability in mathematics, as we’ve known since Gödel’s theorem. But the mathematics that mathematicians usually work on is basically set up not to run into it. But just being “plucked from the computational universe”, my cellular automata don’t get to avoid it.
I definitely wouldn't call him a crackpot, but he does seem to be spinning in a philosophical rut.
I like his way of thinking (and I would, because I write code for a living), but I can't shake the feeling that his physics hypotheses are flawed and are destined to bear no fruit.
But I guess we'll see, won't we?
[1] http://bactra.org/reviews/wolfram/ [2] https://writings.stephenwolfram.com/2020/04/how-we-got-here-...
But I think his articles about Machine Learning are excellent. [2]
[1]https://www.google.com/search?client=firefox-b-1-d&q=%22comp...
[2]https://writings.stephenwolfram.com/category/artificial-inte...
Many of the quantum and general relativity behaviors seem to be some kind of limits (compared to a newtonian universe where you can go arbitrarily small/big/fast/far). Except quantum computing, that one's unlocking even more computation instead so is the opposite of a limit and making it harder rather than easier to simulate...
I don’t know why so many people feel like it would be an optimization?
Storing a position is a lot cheaper than storing an amplitude for each possible position.
One-hot vectors are much more compressible than general vectors, as you can just store the index.
Also, it is momentum and position that are conjugate, not momentum and speed.
I'd be interested to know where those so many other people who feel that would be an optimization are, because I don't often see opinions like this at all, only either rigorous physicists posting equations and papers, or people not knowing anything about it at all to even philosophize about it.
You can’t simulate a molecule at accurate quark/gluon resolution.
The equations aren’t all that complex, but in practice you have to approximate to model the different levels, eg https://www.youtube.com/playlist?list=PLMoTR49uj6ld32zLVWmcG...
I don't think so.
In classical physics, "all" you have to do is tot up the forces on every particle and you get a differential equation that is pretty easy to numerically work with. Scale is a challenge all of its own, and of course you'd ideally need to learn about all the numerical issues you can run into. But the math behind Runge-Kutta methods isn't that advanced (really, you just need some calculus to even explain what you're doing in the first place), so that's pretty approachable to a smart high schooler.
But when you get to quantum mechanics, it's different. The forces aren't described in a way that's amenable to tot-up-all-the-forces-on-every-particle, which is why you get stuff like https://xkcd.com/1489/ (where the explainer is unable to really explain anything about the strong or weak force). As an arguably competent software engineer, my own attempts to do something like this have always resulted in my just bouncing off the math entirely. And my understanding of the math--as limited as it is--is that some things like gravity just don't work at all with the methods we have at hand to us, despite us working at it for 50 years.
By way of comparison, my understanding is that our best computational models of fundamental forces struggle to model something as complicated as an atom.
(1) quantum mechanics means that there is not just one state/evolution of the universe. Every possible state/evolution has to be taken into account. Your model is not three-dimensional. It is (NF * NP)-dimensional. NF is the number of fields. NP is the the number of points in space time. So, you want 10 space-time points in a length direction. The universe is four-dimensional so you actually have 10000 space-time points. Now your state space is (10000 * NF)-dimensional. Good luck with that. In fact people try to do such things. I.e., lattice quantum field theory but it is tough.
(2) I am not really sure what the state of the art is but there are problems even with something simple like putting a spin 1/2 particle on a lattice. https://en.wikipedia.org/wiki/Fermion_doubling
(3) Renormalization. If you fancy getting more accuracy by making your lattice spacing smaller, various constants tend to infinity. The physically interesting stuff is the finite part of that. Calculations get progressively less accurate.
The trick is (as the sibling comments explain) that it involves an exponential number of calculations, so it's extremely slow unless you are interested only in very small systems.
Going more technical, the problem with systems with the strong force is that they are too difficult to calculate, so the only method to get results is to add a fake lattice and try solving the system there. It works better than expected and it includes all the forces we know, well except gravity , and it includes the fake grid. So it's only an approximation.
> Could a competent software engineer, even without knowing the fundamental origins of things like particle masses or the fine-structure constant, capture all known fundamental interactions in code?
Nobody know where that numbers come from, so they are just like 20 or 30 numbers in the header of the file. There is some research to try to reduce the number, but I nobody knows if it's possible.
You can expand that Lagrangian out to look more complex, but that's just a matter of notation rather than a real illustration of its complexity. There's no need to treat all of the quarks as different terms when you can compress them into a single matrix.
General relativity adds one more equation, in a matrix notation.
And that's almost everything. That's the whole model of the universe. It just so happens that there are a few domains where the two parts cause conflicts, but they occur only under insanely extreme circumstances (points within black holes, the universe at less than 10^-43 seconds, etc.)
These all rely on real numbers, so there's no computational complexity to talk about. Anything you represent in a computer is an approximation.
It's conceivable that there is some version out there that doesn't rely on real numbers, and could be computed with integers in a Turing machine. It need not have high computational complexity; there's no need for it to be anything other than linear. But it would be linear in an insane number of terms, and computationally intractable.
I hear it's a bit more complex than that!
https://www.sciencealert.com/this-is-what-the-standard-model...
the thing about Lagrangians is that they compose systems by adding terms together: L_AB = L_A + L_B if A and B don't interact. Each field acts like an independent system, plus some interaction terms if the fields interact. So most of the time, e.g. on Wikipedia[0], people write down the terms in little groups. But still, note on the Wikipedia page that there are not that many terms in the Lagrangian section, due to the internal summations.
[0]: https://en.wikipedia.org/wiki/Mathematical_formulation_of_th...
It's not impossible that the universe is somehow implemented in an "umpteen gazillion bits, but not more" system, but it strikes me as a lot more likely that it really is just a real-number calculation.
Getting rid of the event horizon is simply a question of increasing the angular momentum and/or charge of this object until the inequality is reversed. When that happens the event horizon disappears and the exotic object beneath emerges.
There's a pretty decent argument real numbers are not enough:
So we don't have a set of equations that we could expect to model the whole universe in any meaningful way.
https://en.wikipedia.org/wiki/Newton%27s_law_of_universal_gr...
Maybe still too ambitious, because I haven't heard of such a program.
The author states that "it is short range because the particles that “mediate” the force, the W and Z bosons, have mass;" is misleading as to causality, but I missed the part where they showed how/why it was misleading.
It's interesting to me how fuzzy the definition of quantum physics is. For example, I've seen the description of particles as described by a wave function (e.g. electron position and momentum in an atom) labeled as a quantum phenomenon, but have also heard it, as in this quote, as classical, since it's defined by a differential equation; a "classical" wave. In that view, quantum only enters the model when modelling exchange effects, spin, fermion states etc.
With the former definition, as in the article, you see descriptions of the wave nature of matter, replete with Planck's constant, complex wave function representations etc described as classical.
In short, a massive virtual particle can exist only briefly before The Accountant comes looking to balance the books. And if you give it a speed of c, it can travel only so far during its brief existence before the books get balanced. And therefore the range of the force is determined by the mass of the force carrier virtual particle.
There's probably some secondary and tertiary "loops" as the virtual particle possibly decays during its brief existence, influencing the math a little further, but that is beyond me.
It's really difficult to reconcile "standing waves in empty space" with "stiff fields". If the space is truly empty, then the field seems to be an illusion?
If we think about fields as the very old concept of aether, then it actually makes more intuitive sense. Stiffness then becomes simply the viscosity of the aether.
But I don't think this is where this article is trying to get us!!
I like the speaker on water / styrofoam particle demonstration of standing waves.
I believe this is not dissimilar to the mechanics suggested by the ZPE/antigravity people like Ashton Forbes
Seems generally unhelpful to say 'the weak force is short range because it's field is stiffer!' When you can then immediately say 'well why is the weak force's field stiffer?'
Or: consider where science would be had it operated under your proposed maxime for the past 3 centuries.
I.e. The weak force is short range because it's field is stiffer -> the weak force's field is stiffer because it is more oblong -> the weak force's field is more oblong because it has more sparkles -> it has more sparkles because it ha slower mushiness -> it has more mushiness because ...etc.
We haven't gained anything in that sequence.
I don't think we can answer fundamental questions like this. The fine structure constant is the value it is because without that value we can't have a universe like this. Maybe in some multiverse system the physical laws and constants we know are fluid and can take different values in different universes but in our universe simply because of observation selection effects they can only be what they are.
> The weak force is short range because it's field is stiffer.
May seem like a simple redirection that could go on forever, but we learned that fields can be stiffer, which probably wasn't all that clear. Now we can observe all other forces and look how their fields vary in terms of stiffness — a parameter we might not have thought about before. And by looking in those other places we might find a clue on how to shape an experiment that allows us to vary the stiffness. That could already have useful applications, but also lead to answering the question why some forces have stiffer fields than others.
In reality, almost all of our math was retrodicted (the result of taking observation and creating math to fit it).
So, as you said, we're left with anthropic arguments or religious arguments.
For me, I've ended this song and dance by realizing the crazy math works because it was part of a plan.
The more you look at the math, the more you realize that:
1. We can only work from observation back to the math. There is no consistency to the math, except "these are the rules needed to make a stable, habitable universe."
2. Our current mathematical understanding is mostly approximations and idealizations. Every time we look at the universe at a deeper level, we find exceptions that we are fortunate exist, because they allow for a richer universe than our math suggested should exist. (Quantum mechanics is a good example. Things like quantum tunneling were not imagined 150 years ago, but it allows fusion to take place in the sun at far lower densities than should seem possible.)
So, I agree with you. I'm convinced the real answer will never be found in the math of physics, only in the realm of philosophy and religion.
Edit: I love science and I believe we should keep studying and asking how this all works. But, I feel we can make plenty of progress simply asking "how" it works and realize that at this point, "why" it works seems to be fully unanswerable by science.
Does anyone know when physicists realized that the world is not made of indivisible units called "particles" but waves? Is there a specific experiment or are we talking about the results of many experiments?
Where? I can't find that quote in the article.
> He calls waves with very small amplitude "particles" (for historical reasons).
The closest thing I see is
In a quantum world such as ours, the field’s waves are made from indivisible tiny waves, which for historical reasons we call “particles.”
Note the "indivisible" part. That's not how waves work in your everyday experience. The common understanding of "wave" is based on classical physics, where waves can be scaled up or down arbitrarily. But here you have "waves" which can only get so small, but no smaller, which he then goes on to parenthetically suggest calling "wavicles".
Is coining a new word which is literally a combination of "wave" and "particle" not a way "to imagine them as both wave and particle"?
What he's trying to explain without math is essentially the canonical quantization formalism due to Dirac, circa 1927:
https://en.wikipedia.org/wiki/Second_quantization
It's still the first approach to quantum field theory which physics students are likely to encounter.
His "wavicle" is essentially the field expectation value for a free particle. There is a nice animation (in the non-relativistic limit) here:
https://en.wikipedia.org/wiki/Schr%C3%B6dinger_equation
He seems to gloss over the connection to experiment though. Let's say you shoot an electron through slits in a screen and want to find out where it ends up using a photographic plate; you'll get a single dot somewhere on your plate, not an extended pattern. You can repeat the experiment with a new electron and get another dot, and keep repeating the experiment until all the dots form a pattern, in well known fashion:
https://en.wikipedia.org/wiki/Double-slit_experiment
The "wavicle" explains the pattern, but the pattern is made of dots...
But my problem is different.
Below I use the word “particle” to mean “a three dimensional indivisible unit,” and nothing else. A particle is not a mathematical point as Strassler suggests when he describes a particle as a “dot.” And a particle is not a wave. If Strassler decides to call waves “particles”, waves do not magically become particles. Ever since the scientific revolution we have not explained natural phenomena by magic.
I read Strassler quote again:
“In a quantum world such as ours, the field’s waves are made from indivisible tiny waves, which for historical reasons we call “particles.” Despite their name, these objects aren’t little dots...”
My interpretation of this quote is like this:
> In a quantum world such as ours the field’s waves are made from indivisible tiny waves...
This means that the world is made of quantum fields and fields are waves and not particles [particle are indivisible units, Strassler calls them “little dots”].
This is a clear statement. Strassler is saying that our world is quantum and it is made of fields. Fields are not particles. The unit of study of physics is now fields, not particles. There are no particles in this world because the field is made of waves. These waves are not particles. But they differ from the classical waves because they can only be scaled down to a certain length.
> ...which for historical reasons we call “particles”. Despite their name these objects aren’t little dots [they are not indivisible units with extension].
Strassler’s quote makes it clear that the building blocks of the world are waves, not particles. In this world of ours there are no particles in the sense of indivisible units. It is only that Strassler chooses to call these waves “particles.” This is just a naming convention.
If someone decides to call “monkey” the animal we know and love as a “donkey”, obviously the long eared cute animal will not become a monkey just because someone decided to call it “monkey”. This play on words can only make a monkey out of logic and create confusion. If we are calling an animal with the name of another animal we are only exposing ourself as a sophist.
This is exactly what Strassler is doing. He is intentionally trying to corrupt the meanings of well established words by loading them with new meanings. He is playing naming games. Calling a wave particle does not make the wave a particle. Then why call a wave particle? No sane person would call a wave “particle” unless he has something to hide and wants to deceive us or even deceive himself.
To me, if true, the fact that the building blocks of the world are waves is a huge and fundamental discovery because it proves that the world is not atomic and matterful as Newton assumed. There are no forces acting between particles because particles do not exist.
This is where the problem lies for physicists. Atomic materialism is their professional dogma and they need to save it despite the experiments contradicting it. But this dogma cannot be saved by using sophistry and calling waves particles.
No, the limitation is not length; it's amplitude.
In Dirac's formalism, there is a vector which describes the state of the world, and there are operators which act on that vector. Those operators can create and destroy integer quantities of things. So you can have zero things, or one thing, or two things, or a million things... but not half a thing, or some other fraction. That is the "indivisible" part. The things can be smeared out over macroscopic distances, as in the case of the double slit experiment, but their number is an integer.
But if the story ended there, you still wouldn't have a quantum theory. You would just have a (partially) discrete, classical theory. You could write down a set of differential equations (indeed, wave equations) involving your operators and use them to study how a given vector will evolve over time. The whole thing would be completely deterministic, just like classical mechanics. And yes, it would describe a world made of "wavicles".
Strassler seems to be thinking of that world. But there is one last step you need to take in order to have a quantum field theory.
I like the way Wikipedia tells the story of how it was discovered [1]. Snipping wildly:
Following up on de Broglie's ideas, physicist Peter Debye made an offhand comment that if particles behaved as waves, they should satisfy some sort of wave equation. Inspired by Debye's remark, Schrödinger decided to find a proper 3-dimensional wave equation for the electron. [...] The Schrödinger equation details the behavior of Ψ but says nothing of its nature. Schrödinger tried to interpret the real part of Ψ ∂Ψ / ∂t as a charge density, and then revised this proposal, saying in his next paper that the modulus squared of Ψ is a charge density. This approach was, however, unsuccessful. In 1926, just a few days after this paper was published, Max Born successfully interpreted Ψ as the probability amplitude, whose modulus squared is equal to probability density.
That is what sets quantum theories apart from classical ones. The math is deceptively similar, but once you're done evolving your wav(icl)es, you need to take that last step: compute their amplitude squared to get a probability density.
If you are trying to predict a position, like the position of an electron in the double slit experiment, you won't get a set of coordinates; you will get a probability density covering the entire photographic plate. That probability density will look like a wave interference pattern, because that's exactly what it is: it's a pattern of interfering waves of probability.
So the "wavicles" are not particles; they encode the probability of detecting a particle. When you do the experiment, each particle shows up as a dot, and you can do other experiments to convince yourself that electrons really are point-like, at least up to the resolution achievable with the largest accelerators built to date.
Pondering what that all means - what quantum theory is telling us about the nature of reality - will lead you to a swamp known as "interpretations of quantum mechanics" [2].
[1] https://en.wikipedia.org/wiki/Schr%C3%B6dinger_equation#Hist...
[2] https://en.wikipedia.org/wiki/Interpretations_of_quantum_mec...
Whether you call that stiffness or mass is a little beside the point IMO -- it shows up in the Yukawa force as an exponential dependence on that parameter which means the force quickly decays to zero unless the parameter is 0.
x = 2 # sets x to two
Where in my comment is there any math? It's all physical concepts. No mathematics at all. Because the purpose and intent of my post was to point out that the role mass plays is identical to that of stiffness in other contexts. That's it, and he takes a very circuitous route to pointing that out.
It's like the opposite of what you described. If you don't know what "mass" and "stiffness" are you should probably understand those before attempting to understand quantum field theory. It's not condescension. The analogy holds only if you really understand both concepts.
The algebra is beside the point.
"it shows up in the Yukawa force as an exponential dependence on that parameter which means the force quickly decays to zero unless the parameter is 0"
It tells nothing to people who don't know the equation you are talking about and tells nothing new to people who know it.
Is there an ELI5 version of this? I think the article tries, and it's always cool to see physics described from a different vantage point.
My ELI5 version would be: fields with a massive gauge boson are "dragged down" in energy by the mass of the boson, so interactions propagate as if they have negative energy. What does a negative energy wave propagation look like? Similar negative energy wave propagations in physics are evanescent waves and electron tunneling, both of which have exponential drop-off terms, so it makes sense to see an exponential factor in massive boson interactions.
https://profmattstrassler.com/2025/01/10/no-the-short-range-...
Isn't this called "equivocation" in logic?
Do virtual particles decay?
On top of that, if we find something that behaves nothing like what people meant when they said aether, then is it really aether?
Overall, we can't really have 'conclusive evidence' against any mechanism, as long as our observations might possibly be simulated on top of that mechanism. So as far as evidence goes, 'what really exists' might be higher-dimensional strings, or cellular automata, or turtles all the way down, or whatever.
Instead, physics has some number of models (either complementary or competing) that people find compelling, and mechanisms on top of those models to explain our observations. If you did come up with a modern aether theory, you'd have to come up with a mechanism on top of it to explain all the relativistic effects we've observed.
It's simpler not to have a medium. The field components transform a certain way under coordinate transformations, and that's all you need.