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Inside the proton, the ‘most complicated thing you could possibly imagine’

quantamagazine.org

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Re: Inside the proton, the ‘most complicated thing you could possibly imagine’

#201

Post by gumby »

emmelaich wrote: post #139
gumby wrote: post #20

Earlier quoted context omitted.

> The real question is, are we running on bare metal, in a VM, or in a container? We can't be running on the bare hardware; there is clearly an OS enforcing the hardware abstraction (e.g. every electron is identical). But is each universe its own process? What happens if you fork()?

> every electron is identical That's an illusion; there is only one electron.

That’s how the kernel implements it anyway; every time you do a syscall to look at it you get a different pointer to the same 'struct lepton'.

Re: Inside the proton, the ‘most complicated thing you could possibly imagine’

#202

Post by CoastalCoder »

blueprint wrote: post #153
Balgair wrote: post #126

Earlier quoted context omitted.

Yes, yes, I also understand this. But why are they in units of 1/3(e). Why are down quarks not -0.398390847895...(e) and up quarks not +0.6234098129034809234...(e). Why do they add up so damn neatly?

when you understand quantum theory correctly, you will realize that particles don't exist by themselves. They are a temporary localization. this means that the number of quarks inside a proton is not actually fixed. when a particle becomes disentangled with the system, that localized it, there's no longer a particle I mentioned this recently, in the context of the laziness in language, leading to the miseducation of…

HN is a great training ground for learning how to present arguments in a compelling, engaging manner.

Re: Inside the proton, the ‘most complicated thing you could possibly imagine’

#203

Post by Mistletoe »

andy_xor_andrew wrote: post #18

I just had a really stupid thought, after finishing reading the article. So, the electron is an elementary particle, right? Compared to the proton, the electron is "simple", yes? Despite this difference in complexity, an electron has a charge of -e and a proton has a charge of +e. They are exactly complementary regarding charge (if I am understanding right, I am not a smart person). my question is... why? why must pr…

I believe the end of my physics textbook in college just said “be grateful that the charge on the electron is what it is because without it our universe wouldn’t exist if it was even slightly different” or something to that effect.

Our universe may be the trillionth trillionth one created and we are in an anthropomorphic universe just like we are on an anthropomorphic planet. It always makes me grateful.

>The charge on a proton is +1.602 x 10-19 C, and the charge on an electron is -1.602 x 10-19 C.

Re: Inside the proton, the ‘most complicated thing you could possibly imagine’

#204

Post by blueprint »

CoastalCoder wrote: post #202
blueprint wrote: post #153

Earlier quoted context omitted.

when you understand quantum theory correctly, you will realize that particles don't exist by themselves. They are a temporary localization. this means that the number of quarks inside a proton is not actually fixed. when a particle becomes disentangled with the system, that localized it, there's no longer a particle I mentioned this recently, in the context of the laziness in language, leading to the miseducation of…

HN is a great training ground for learning how to present arguments in a compelling, engaging manner.

that may be true, but I'm already highly trained at that. But hey, what if you just ratchet up the difficulty to infinity. Then it will train people even better. Either that or it'll destroy the community because you dont have any criterion of right and wrong in your claim.

It doesnt matter how correct people are. The more correct people are the worse they're treated. The better we get at presenting true arguments the more you will resent us and the more you have no choice but to react with violence (being unable to admit your lie), as HNers do now with trap counterarguments and gaslighting. No wonder suicide is on the rise.

Re: Inside the proton, the ‘most complicated thing you could possibly imagine’

#205

Post by hwillis »

seeknotfind wrote: post #140
Rayhem wrote: post #54

Earlier quoted context omitted.

> I have no doubt quantum physicists know what they are talking about but...I always think it is the kind of excuse a schoolkid would give their teachers for their calculations being wrong. Just to emphasize how extreme this dichotomy is, not only is quantum mechanics correct (in that it's a predictive model), it's the most correct physical theory humans have ever devised in that the measurements there have more sign…

So many significant digits includes a level of self-consistency of the model, since we are assuming the model to some degree in order to measure it. Though in this case, it's not the calculations that are wrong, but the model, we hope is wrong. That is, a new perspective and a new way of thinking about things may reveal more. Of course, we are always fighting against the irreducible complexity camp. However, the fund…

> So many significant digits includes a level of self-consistency of the model

No, that's incorrect. The specific measurement -the most accurate scientific prediction humans have ever made, the anomalous magnetic moment- is only to 1 in 10 trillion. The magnetic moment (think moment of inertia) is the ratio of force from the magnetic field to the mass of the electron. You put an electron into a magnetic field, and it'll turn to face the field at a certain speed. If you stick the electron in a vacuum, it overshoots (because of rotational momentum) and ends up wobbling back and forth at a specific frequency. That's how MRIs work; they make a big magnetic field (stronger on one end) and then measure how many electrons are wobbling in different areas, since the electrons in high-strength fields wobble faster.

Specifically, you expect the wobble to get ~2.8025 GHz (similar to a microwave oven) faster for every 1000 gauss (please, no jokes about teslas). It's very convenient to measure a difference in frequency, since you can just measure the drift over time. Because that frequency is relatively high it takes about 30 minutes for the frequency to drift off by a half-cycle and totally cancel out your reference.

And it's super easy to get a reference frequency, too. It's just the charge of an electron divided by 2x the mass of an electron. Did you do this experiment in physics class? https://www.youtube.com/watch?v=Kcn2VgBNJjg

Then you measured the charge/mass ratio of an electron. A clock that's accurate to 1 in 10 trillion is also not a big deal, although unless you have an oscilloscope in your house its probably more accurate than any clock you own. Still, you can buy a better Phase Locked Loop for a couple bucks.

If you just wanted to measure the difference, you don't need that much precision, though. The correction from quantum mechanics is pretty large, relatively speaking: ~0.16%. Even the next several digits are super easy, and it's only those last ones that you really need to bust out the liquid helium.

Lawrence and Livingston made the first cyclotron out of literal junk: https://upload.wikimedia.org/wikipedia/commons/6/61/4-inch-c...

And it really doesn't take much more than junk to get to that 0.16% accuracy that lets you see that a classical prediction of the electron is just VERY wrong. But if you listen to those wizards with the bongos, suddenly they're really, really right about what that difference is: https://en.wikipedia.org/wiki/Vertex_function

Re: Inside the proton, the ‘most complicated thing you could possibly imagine’

#206

Post by ynniv »

andy_xor_andrew wrote: post #18

I just had a really stupid thought, after finishing reading the article. So, the electron is an elementary particle, right? Compared to the proton, the electron is "simple", yes? Despite this difference in complexity, an electron has a charge of -e and a proton has a charge of +e. They are exactly complementary regarding charge (if I am understanding right, I am not a smart person). my question is... why? why must pr…

Huh. It would make a lot more sense if the "complicated" proton was +3 and always paired with three "simple" -1 electrons. Maybe someday we'll find the electron is really three of some even more fundamental particle.

Re: Inside the proton, the ‘most complicated thing you could possibly imagine’

#207

Post by hwillis »

julianeon wrote: post #191
mcmoor wrote: post #69

Earlier quoted context omitted.

It's interesting that semiconductor engineers have to directly wrestle with the magic that's quantum tunneling. This theory is really not just a theory.

The other famous example is PET scanners, which actually use a form of antimatter: positrons (the antimatter counterpart of electrons).

You don't even need that. The prediction he's referring to as most accurate is the magnetic moment of the electron, which is used in plain old MRIs. If we didn't have the quantum mechanical correction, all of our MRI images would be distorted. Only by a few pixels, but it'd be noticeable!

Re: Inside the proton, the ‘most complicated thing you could possibly imagine’

#208

Post by clankyclanker »

andy_xor_andrew wrote: post #18

I just had a really stupid thought, after finishing reading the article. So, the electron is an elementary particle, right? Compared to the proton, the electron is "simple", yes? Despite this difference in complexity, an electron has a charge of -e and a proton has a charge of +e. They are exactly complementary regarding charge (if I am understanding right, I am not a smart person). my question is... why? why must pr…

So, PBS Space Time did a video on this “fine tuned universe” theory and it, like all of their videos, is great. The concept seems to be that in an unbalanced universe, life couldn’t form, and we’d be incapable of having this conversation. So, either there are infinite universes and we exist as a result of being in the right one, or there’s one universe and we exist as a result of the one we’re in being right. Either way, we’re pretty lucky.

https://youtu.be/YmOVoIpaPrc

Re: Inside the proton, the ‘most complicated thing you could possibly imagine’

#209

Post by dvsfish »

rapjr9 wrote: post #190

When I read articles like this I can't help but think that if they were probing apples with a hammer, using stronger and stronger hammer blows, they would conclude that apples are flat and mushy. With stronger hammer blows they'd find the apples are paper thin and hot. How do they know when doing these collision experiments that some of the resulting particles are not popping out of the CMB and aren't actually in the…

I literally was just having a foggy version of this exact same thought whilst reading the article. Especially

> "Researchers recently discovered that the proton sometimes includes a charm quark and charm antiquark, colossal particles that are each heavier than the proton itself."

You articulated my feeling better than I could. Surely this is something the researchers have accounted for and there's a good explanation (whether I can actually understand it is another story)

Re: Inside the proton, the ‘most complicated thing you could possibly imagine’

#210

Post by timeagain »

clankyclanker wrote: post #208
andy_xor_andrew wrote: post #18

I just had a really stupid thought, after finishing reading the article. So, the electron is an elementary particle, right? Compared to the proton, the electron is "simple", yes? Despite this difference in complexity, an electron has a charge of -e and a proton has a charge of +e. They are exactly complementary regarding charge (if I am understanding right, I am not a smart person). my question is... why? why must pr…

So, PBS Space Time did a video on this “fine tuned universe” theory and it, like all of their videos, is great. The concept seems to be that in an unbalanced universe, life couldn’t form, and we’d be incapable of having this conversation. So, either there are infinite universes and we exist as a result of being in the right one, or there’s one universe and we exist as a result of the one we’re in being right. Either…

I can’t get behind all these fine tuning arguments. Who’s to say what life might form if the proton had a charge of 1.01e or if the fine structure constant was 1/138? Something about the line of reasoning that there is a multiverse and we just happen to live in favorable conditions reminds me of Pascal’s wager. It doesn’t do anything other than unfalsifiably assure the wagerer that they are important
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