Comment by XorNot

Comment by XorNot 3 days ago

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Urgh, I'm half way through this and I hate it.

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?)

lokimedes 3 days ago

In all honesty, this gives a delightful if frightening look into how physicists are thinking amongst themselves. As a (former) particle physicist myself, I can’t remember the number of times an incredulous engineer has confronted me with “the truth” about physics. But you see, for practicing physicists, the models and theories are fluid and actually up for discussion and interpretation, that’s our job after all. The problem is that the official output is declared to be immutable laws of nature, set in formulae and dogmatic conventions. That said, I agree that he is trading one possible fallacy for another here, but the beauty of the thing is that the “stiffness” explanation is invoking less assumptions than the quantum one - which physicists agree is a “good thing” (Occam’s razor).

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  • xigency 3 days ago

    There definitely seems to be a modern trend of over complication in physics along with the voodoo-like worship of math. Humbly enough, people have only come to understand the equations for an apple falling out of a tree within the last 500 years, and that necessitated the invention of Calculus.

    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).

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    • selecsosi 3 days ago

      Having studied undergraduate physics, I think this viewpoint is inverted from the realities of the matter. It is less that the math is complicated and more so these are the relevant tools invented for us to model the experimental results we obtain post discovery/formalization of SR/GR/Quantum experiences. There are computers that can run these simulations but they are infeasible to model large scale processes. That is the reason people are looking for more than numerical solutions to problems, but laws and tools that can simplify modeling large scale emergent behavior that it would be infeasible or unnecessarily complicated to do with numerical simulation. These tools are the more straightforward approach

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      • xigency 3 days ago

        It's evident and obvious in any of these explanations that the equations and properties of math are taken as true a priori, not grounded on observation (in their invocation).

        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.

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        • selecsosi 2 days ago

          I think that's more your interpretation/experience rather than the intention of the tools. Those constants and coefficients are there because the math is describing the shape of the solution based on logic, mathematical object rules, and symmetry/conservation laws and needs to be "grounded" to make them physical.

          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.

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    • numpy-thagoras 3 days ago

      Voodoo worship of math? I am getting a bit tired of that sentiment, especially around string theory.

      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.

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      • xigency 3 days ago

        If you're going to say that you need to study math exclusively for many years to understand your formulas then you are not using abstraction well.

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        • numpy-thagoras 17 hours ago

          I don't think that's what I would say, but if that's what you are anticipating, then I don't think you have a very good take, either. I don't even think we'd resolve our problems with physics if everyone were a mathematician first. However, it will always take many years of training to understand some of the major equations to a sufficient degree.

          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.

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  • numpy-thagoras 3 days ago

    Yeah, the whole 'immutability' thing is just a front for the layperson, and that's honestly fine. However it does generate a weird set of expectations and culture shock when you cross that barrier into proper physics and you see people don't consider these things immutable, the best you've got is instrumentalism and functionalist treatment of observables. These worldviews have been a source of too many red herrings for the unprepared.

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andyferris 3 days ago

I agree this doesn't gel well with the pop-science approach.

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).

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Y_Y 3 days ago

I had very much the same feeling. Honestly this might be all true, but it's got a vibe I don't like. I did QFT in my PhD and have read plenty of good and bad science exposition, and it doesn't feel right.

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.

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dist-epoch 3 days ago

> introducing a lot of new ideas without grounding

The grounding is 3 years of advanced math.

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SpaceManNabs 3 days ago

> 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

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.

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  • XorNot 3 days ago

    > 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 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.

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