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Comment by HarHarVeryFunny | Hacker News Reader

Maybe "Higgs soup" is a particularly bad "phib", or mental model, but OTOH I'm sure there are approximately zero non-physicists even aware that the "Higgs Field" is a thing, or at least a thing in the minds of Physicists.

I think phibs, or more generally science-fibs, are mostly harmless and useful. These are mostly introduced at high school level where a simplified (even if flawed) explanation of something can at least give a rough understanding, and introduction to scientific thought process. Better to go through life thinking that color perception is based on light frequencies, and evolution selecting more-fit individuals, than to have no appreciation of how the world works.

I suppose "Higgs soup" is particularly bad in not being a simplified version of the truth, just a poor mental model, but the topic is so esoteric that it seems harmless.

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When you say “X is just a simplified version of the truth, a poor mental model”—well, so is everything else in physics.

Everything is a model, if you look closely enough. Atoms, electrons, strings, fields, waves, what have you. The only ground truth is “if we try X, then we observe Y reliably”; we naturally tend to make up models (stories) that make sense to us humans as a shortcut to that truth—that’s just how our minds work—but the entities that appear in those models themselves do not gain absolute existence in some objective reality merely from that.

Tomorrow there will be a better model that may look nothing like the current one; there can be multiple conflicting models that fit different purposes; and if the incompleteness theorem is right then it shall continue forever as we cannot ever build a single provably correct and complete model of the system from within that system. The point of a map is that it does not span the entire extent of the territory.

All models are wrong, some are useful.

-George Box

I'd go further and say that many "theories of everything" that try to remove context from the models, in fact obscure the fundamentally useful approximations. Unless you really need that complicated model for the last fractional percent accuracy, leave it out! Also, knowing (or controlling) the context withing the model is being used is often critical to making something work well for a reasonable cost in a reasonable time.

Indeed - the most useful (as in, most-used) models strip out darn near every calculation and boil things down to a very simple rule-of-thumb approximation.

For example, plumbers just ballpark the pressure of water due to elevation to "half a PSI per foot". Their 1/2psi "model" gets them close enough without making them use a calculator. Their 1/2psi "model" gets them close enough, with an appropriate safety factor built-in, without making them use a calculator. Even though really it's much closer to 0.433psi per foot of water column.

But really it's much closer to (((((aT+b)*T+c)*T+d)*T+e)*t+f)/(1+h*T) * g * 0.3048 * 0.453592 psi per foot of water column depending on what the temperature is and what gravity is where you are. And for further precision you'd need to integrate this equation with respect to T and gravity along the height of the water column, or use an even more precise model because the constants a through h are still doing a lot of "heavy-lifting" hiding and abstracting away other hard-to-measure physics phenomena. You'd also have to adjust for impurities in the water, as that will change the density as well at these precisions. It also only applies to water that's not moving, moving water will have a lower psi per foot due to friction.

Obviously plumbers certainly wouldn't find it useful to have to replace their "half-a-psi-per-foot" mantra with something involving an equation to determine the density of water (generally considered incompressible anyways) as a function of its temperature. The amount of situations which need the more complex models are very few and far between.

But we do still need them! A "theory of everything" would be fantastically wonderful for opening up generation and validation of new, useful, rules-of-thumb for many scientists and engineers.

T = temperature of water in C

a=-2.8054253⋅10^-10

b=1.0556302⋅10^-7

c=-4.6170461⋅10^-5

d=0.0079870401

e=16.945176

f=999.83952

g=9.81 m/s^2 (variable depending on where you are on or off the planet)

h=0.01687985

I'm clearly a physicist through-and-through, I read "half a psi per foot" and wondered if it was ψ or Ψ, and why a plumber would use a Greek letter for anything.

I'm a European physicist/electronics engineer/software developer and I just wondered what was wrong with 0.1 bar per metre.

Haha! Thank you, edited for clarity for a wider audience.

I’d be the first to admit that “theory of everything” is infinitely compelling to me, but increasingly I think it also deserves caution.

It would certainly open many new avenues to explore, and potentially bring lots of innovation.

However, to prove it you would need infinite resources and infinite time—in other words, you will never prove it, so within the framework of physics you will not assume it is complete and correct and absolute truth.

But there are people who will assume just that, they’ll see how well it works and what progress it brings and say “that’s it guys, we have finally arrived at truth!” When they see something that doesn’t fit in the model (say, consciousness or free will), they will say it doesn’t exist and influence policy decisions based on that. When they see someone using another theory or even suggesting there can be others, they will ridicule them.

As map is never the territory, any model is always going to be a local maximum, and a particularly high local maximum followed by a steep trough might make it difficult to reach the next one.

The Incompleteness theorem is a about formal theories, so why does the particular ground truth of observation hold as a sound, complete metatheory?

They might not immediately recognize "Higgs field" per se, but lots of people have heard of the "Higgs boson" due to all the press about its discovery at CERN. Most of them heard in the next sentence that it has something to do with giving particles mass. I'd guess the vast majority of public who is broadly interested in science has heard of it.

I think anyone who read about the building or operation of the Large Hadron Collider has a faint understanding of Higgs. To explain the boson educators tend to mention the field as well.

You can get a feel for how it works in this [section][1] of the wikipedia article. Have to know what things like "mass term" mean, though, so there's quite a lot of background required.

[1]: https://en.wikipedia.org/wiki/Higgs_mechanism#Abelian_Higgs_...

I don't know, I think its ok to just tell someone that its out of their own grasp to understand the thing at hand and leave it at that. Giving someone a surface level "understanding" ultimately marks them as an idiot in the topic at hand because they will go on to parrot their useless understanding for what purpose?

There's a clip from a short documentary about Richard Feynman in which the interviewer asks him to explain what's going on when you try to push two magnets together head-to-head. Feynman basically says that he could tell you a story like "there are rubber bands pulling the magnets together," but it would be a lie and that if you really want an explanation you have to learn the physics.

https://www.youtube.com/watch?v=MO0r930Sn_8

That's a nice clip.

I think his description of the nature of explanations is relevant here though. Most phenomena, that one might like explained, or wish to understand, aren't as irreducible (at least in terms of things familiar to the questioner) as the fundamental forces!

In terms of education, explaining things at one level of reduction, even if there is more that could be said, meaningfully increases the knowledge of the student (and allows them to ask the next question, should they be interested). This really isn't the same as an analogical "explanation" that in fact explains nothing.

the important thing is to give people a model, not just tell them a fancy story (that they can repeat later without it helping them)

of course, it's easy to say that and hard to come up with good but simple models on the spot, but people don't gain knowledge by learning opaque phrases (that's how we got the whole "quantum woo" epidemic a decade or two ago)

Spare me your petty questions! They spring from a brain too meager to comprehend my reality. Now taste my power!

I think it depends on the topic. Of course there are always going to be pop-sci magazines trying to explain things like quantum physics to the layman (as if scientists themselves really understand it), so no way to avoid this, but maybe not a lot of value either, even if people enjoy thinking they understand something.

For simpler and more accessible topics though, like the examples I gave, I do think there is value in teaching partially-correct simplifications. For one thing, you have to start somewhere, so if some partial understanding is what sparks some kid's interest into pursuing the sciences, then that is a good thing.

Maybe more importantly(?), given that most people won't be going into science-based jobs, is just having some base level of scientific literacy, especially in a world (particularly the USA) where religious belief and conspiracy theories, rather than rational thought, seem to be in danger of dominating society.

I agree with you on just about everything you wrote, except the following passage which neatly sets up the widespread conspiracy theories and erroneous religious beliefs that currently plague our civilization.

>trying to explain things like quantum physics to the layman (as if scientists themselves really understand it)

There's this common misconception that physicists somehow don't understand quantum mechanics. The problem with quantum mechanics (and a whole host of other experimentally-supported theories) is that they describe things so completely removed from our everyday experience (and indeed, occur in regimes that human beings have never experienced even indirectly until the last 100 or so years) that our everyday intuition is wrong every time.

But if you understand the math of quantum mechanics, and you understand how the experiments relate to the math, then you understand how quantum mechanics works. Its not actually that complicated, its just weird.

There are ~1900 PhDs in physics awarded every year, so certainly, tens of thousands of people across the world do understand how it works. Now, if you're going to quibble and say "do the scientists understand what spin really is?" then congratulations, you've just reinvented Humean skepticism, I guess human knowledge reached its maximum extent in 1748.

> But if you understand the math of quantum mechanics, and you understand how the experiments relate to the math, then you understand how quantum mechanics works. Its not actually that complicated, its just weird.

OK, but is that really understanding, or just an ability to crank the handle of the model and make a prediction? How should we interpret what is going on? What to make of observational wave function collapse, or long-distance quantum entanglement (which seems completely at odds with our understanding of space and time)?

I'm too much an instrumentalist to give you an unbiased answer.

My view is that, as it pertains to any theory, the ability to make reasonably accurate predictions within a given region, and reasonably accurately describe the region where those predictions are correct is understanding.

I don't believe our knowledge is complete, because the universe is effectively infinite, so there's room for effectively infinite combinations and permutations of phenomenon even within our understanding. But when we encounter something that contradicts our understanding, that doesn't mean we didn't understand anything we experienced before. It just means that our overall understanding was incomplete.

it's not black and white. we understand plenty! (eg. QED, semiconductors, lots of quantum optics, etc.) and then there are more murkier areas (strong forces, QCD, Higgs) and then there are the untamed beasts that eat their young and season it with Nobel laureates (fundamental questions, structure of the electron, SUSY, things beyond the standard model)

> Better to go through life thinking that color perception is based on light frequencies

wait, is it not?

> evolution selecting more-fit individuals

Do you mean that it is simplification from "more-fit individuals are more likely but not certain to be selected"?

We sense color by light frequency, but our actual perception of it (what color we think something is) is far more complex.

Here's a classic illusion. The strawberries in this photo are not red.

https://petapixel.com/2017/03/01/photo-no-red-pixels-fascina...

This has to do with "color constancy" - we learn to see the same object in different lighting conditions as being the same color, even thought the light frequencies reflected may be different.

We basically see what we predict we'll see.

Evolution really acts on populations, not individuals, and often it's more about the environment changing than the population. Basically isolated populations of a species interbreed and (as a population) accumulate genetic changes as long as they are mostly benign. Then, once in a while ("punctuated equilibrium") something in the environment changes - food supply, pathogen, weather, etc, and some of these long-term accumulated changes (maybe collectively) suddenly become important and result in one population surviving/thriving better than another.

"is based on light frequencies" is still true, right

"is based directly on light frequencies with no other transformation" would be wrong

Yes - it's the light frequencies that let us differentiate colors, but we're not always going to perceive the same color each time our frequency detectors (cones) detect the same frequencies, since color perception is more about the whole scene and what we're experienced before.

Another simple experiment that proves this is when you put on color tinted sunglasses or ski goggles - initially everything will seem color tinted, then after a while colors go back to normal.

It's not just color - the whole idea that our eye works kind of like a camera and what we see is what is is really there is wrong. There have also been experiments done with prism-based inverting goggles that make everything look upside down... It turns out that after you've worn them for a while then everything flips the right way back up again and looks normal to you, even though the googles didn't change.

I assume what they meant was that only some colors are pure frequencies, and most are more complex waveforms. As the sibling comment gestures at, "magenta" is the sum of a pure blue wave plus a pure red wave.

"Color" also can refer to several different phenomena which were historically conflated in a way that made teasing apart certain observations difficult. It's a property of objects (apples are red), a property of light (lasers are red) and a property of perception (I see red).

it's the underlying physical phenomenon. but color is apparently more in your head (brain/mind) than in the light itself.

With that approach, literally everything is in your head. Physics itself exists nowhere but in the heads of humans. Even "light itself" exists in our heads - it's just a mental construct that we use to describe certain kinds of electromagnetic energy that our bodies react in certain ways to it. "Color" is no closer of farther to the underlying reality than "light".

> literally everything is in your head.

yes it is. in some form. specifically, in model form.

most things are modeled by our heads. our culture, for the most part, teaches all of us how to do this.

so i'm saying color is a lot more like "flavor", or "texture" in a broad sense.

the funkiest difference is that in the frequency viewpoint, color is linear. however in color theory it's a wheel!

>wait, is it not?

What frequency is magenta?

Well, we have three types of color "cones" in our retina, sensitive to different overlapping parts of the frequency spectrum, so the sensory input for any given color (mix of frequencies) of light is going to be those three types of cones all firing to varying degrees.

http://hyperphysics.phy-astr.gsu.edu/hbase/vision/colcon.htm...

So, since magenta is a mix of red and blue, our "red" and "blue" cones will be most active, but also our "green" cones since its frequency sensitivity also includes red and blue.

Some people have 4 types of color cones, not 3, and can therefore differentiate colors (mixes of light frequencies) that normal people can't.

But, anyways, our brains neural inputs when seeing various colors does not directly correspond to how we perceive them.

"is based on light frequencies" is still true AFAIK, it is just not a nice 1:1 match of all colours to frequencies.

Is there a mental model analogy generator? As in it just generates strange/nonsensical analogies to poke the envelope?

E.g:

Higgs-fire: burning mass to generate time/gravity ...

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