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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’

#411

Post by ruszki »

awestroke wrote: post #361
coldtea wrote: post #359

Earlier quoted context omitted.

Not a physisist, but "consistency with the model" doesn't mean "because that's how some arbitrary model says it should be". It's more like: "Because we have arrived at a model that describes well most other aspect of those particles and their behavior, and has verified predictive power, and given the constrains and calculations based on that model, that's what its charge would be".

Still does not explain "why"

There are causal links, but we always have axioms for which either there is no reasons, they are just how they are, or we don't know the reasons, we have just experimental evidence for them. At the end, the answer to "why" is always, because they are just how they are.

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

#412

Post by notahacker »

knightoffaith wrote: post #283
notahacker wrote: post #142

Earlier quoted context omitted.

Nope, the "god of the gaps" critique has nothing to do scientific discovery being a route to omniscience, something only some religious figures have ever claimed to have even the possibility of access to. It's the set of things religions claim the only explanation/evidence for repeatedly shrinking, as we found explanations for weather that have more predictive power than "the wrath/favour of the gods", found cures fo…

>It's the set of things religions claim the only explanation/evidence for repeatedly shrinking I haven't read The God Delusion or wherever the "god of the gaps" critique originated - what is this actually referring to? Are we just talking about like, pagan polytheistic explanations of natural phenomena? What serious Christian or Buddhist thinkers using religion to explain things like weather or medicine are being ref…

> I haven't read The God Delusion or wherever the "god of the gaps" critique originated - what is this actually referring to?

A rare point of agreement between Nietzsche and the evangelist Henry Drummond was that the Christian apologetic approach of "ah, but that hasn't been explained yet, so it must be God's will" to all the discoveries of the Enlightenment wasn't a very impressive one. Not least because of the tendency of gaps to cease to be gaps.

Ultimately "the more we learn, they more we learn we don't know", to quote the OP is a route to agnosticism not a belief in a particular deity, and it's particularly hard to see an omipotent, benevolent God who created man in his own image in the incomprehensibility of quantum indeterminacy to the average layman (although I'll give credit to the creativity of those suggesting that three quarks must be proof of the Trinity)

> What serious Christian or Buddhist thinkers using religion to explain things like weather or medicine are being referred to here?

It'd be easier to ask what serious theologian said "nope, this stuff about the weather being controlled by divine fiat and pestilence being a punishment for the Fall is just stories and actually you might be able to alter them - perhaps even in your favour - as soon as you stop praying and start doing." well in advance of the accompanying science? Augustine, since you're apparently a fan, was pretty confident that the problem of pestilence was the product of a literally occurring Fall involving two actual First People, which doesn't square very well with evolutionary biology.

Monotheism hasn't quite had the problem of people landing on the moon god, but it's fair to say that what many mainstream monotheists believe today has changed considerably in scope from what mainstream monotheism purported to explain for most of its existence.

> As early as St. Augustine, writing around ~400, and one of the most influential Christian thinkers, we have discussion of the account of creation in Genesis being metaphorical

Sure, Augustine made four different attempts to explain Genesis because even in his time the six day account - still an article of faith for many other Christians even today - didn't make much sense. None of them involved evolution from apes, and he still ended up with Adam and Eve being literal people who caused suffering for everyone [and everything] else via Original Sin.

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

#413

Post by amelius »

oldandtired wrote: post #317
riwsky wrote: post #281

Earlier quoted context omitted.

A proton, electron, and a neutron walk into a bar…

After about 15 minutes, the neutron has changed into another proton and electron, so bar now has a bigger party on its hands.

How do they split the bill?

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

#414

Post by foldr »

coldtea wrote: post #397
foldr wrote: post #382

Earlier quoted context omitted.

I think that was a fairly idiosyncratic point of view of Feynman's. In actual scientific practice you can find hundreds of examples of published scientific papers that address 'why' questions. Here are a couple of completely random examples: https://link.springer.com/article/10.1007/s11207-009-9338-5 https://www.mdpi.com/2624-8174/4/3/63

They answer the why's with the same way @hansbo complained about not answering the why, e.g: " We show that the symmetries of this non-commutative space unify the standard model of particle physics with (2) chiral gravity. The algebra of the octonionic space yields spinor states which can be identified with three generations of quarks and leptons. The geometry of the space implies quantisation of electric charge, and…

It's not uncommon for a scientific paper to raise a question without fully answering it (science is hard). The point is that actual scientific practice does not appear to care about any distinction that can usefully be described as a distinction between 'how' and 'why' questions. You can keep asking 'but why?' ad infinitum and never arrive at a fully satisfying explanation. However, the same is also try of 'but how?' We will find no ultimate answers, but the questions that stimulate scientific research certainly seem to include 'why' questions.

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

#415

Post by zahllos »

coldtea wrote: post #359
hansbo wrote: post #356

Earlier quoted context omitted.

I am reading this as "it has to be this way, or the model does not hold", but it does not explain why. What causes it? Consistency of a model cannot be the ultimate reason, right?

Not a physisist, but "consistency with the model" doesn't mean "because that's how some arbitrary model says it should be". It's more like: "Because we have arrived at a model that describes well most other aspect of those particles and their behavior, and has verified predictive power, and given the constrains and calculations based on that model, that's what its charge would be".

Exactly this. Or to put it another way we don't actually know how the rules of the universe work. So we can't follow a process of deductive reasoning that "why" follows from this or that implication.

Take quantum mechanics. This came out of observations that particles exhibited wave-like behaviour. Mathematics predicts certain things when you start to apply the wave equation. These are then experimentally verified and the model is shown to be pretty good, although it has some deficiencies like not fully linking up with relativity. There are some doubts in some areas of what it predicts as well from what I understand from talking to researchers.

As the article says the original model was that protons were fundamental particles: nothing smaller. This model held up for quite some time but then observational data demonstrated it was insufficient. Same with the three quark model. Knowing the various deficiencies we might go so far as to say "the model that a proton is a +1 charge is good enough" and use that because that works for many situations and that's as much as we need. Although of course, there are always scientists looking to complete the picture.

Science is the incremental acquisition of knowledge through observation and experimentation - and there's an awful lot we haven't figured out.

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

#416

Post by sullyj3 »

hansbo wrote: post #356
importantstuff wrote: post #336

Earlier quoted context omitted.

No one who has replied to your question has got the right answer. https://physics.stackexchange.com/questions/21753/why-do-ele... has the right answer. There are multiple aspects to this argument, but essentially, the symmetries of your system force the charges in the Standard Model (quarks and leptons) to be the way they are due to gauge anomaly cancellation. If you believe in quark confinement, which is extremely w…

I am reading this as "it has to be this way, or the model does not hold", but it does not explain why. What causes it? Consistency of a model cannot be the ultimate reason, right?

Whenever you're asking for an explanation this deep in the ontology stack, you need to think about what kind of explanation would be satisfying to you, and whether you can reasonably expect intuitive answers in domains that lie far outside of your everyday experience. Human brains aren't built to grasp this stuff intuitively.

At a certain point, the reason we like some particular wacky physical model is always going to be "it has the best combination of explanatory power and simplicity"

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

#418

Post by ronald_raygun »

Rayhem wrote: post #54
blackhaj7 wrote: post #49

I have no doubt quantum physicists know what they are talking about but when I read stuff like: “changes its appearance depending on how it is probed" "you can’t even imagine how complicated it is" "the proton contains traces of particles called charm quarks that are heavier than the proton itself" I always think it is the kind of excuse a schoolkid would give their teachers for their calculations being wrong

> 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…

Just because it’s quantitatively accurate doesn’t mean it’s “true”. Like a fun fact I like is the geocentrism was extremely accurate in terms of astronomical predictions when heliocentricism came about (it was actually more accurate for a while).

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

#419

Post by lostemptations5 »

fiddlerwoaroof wrote: post #343
lostemptations5 wrote: post #294

Earlier quoted context omitted.

They are arbitrary in the sense that we could just change them and the universe wouldn't fl appart -- or are they derived from aonething deeper.

The obvious way in which those constants are arbitrary is that the meter is just a random length we compare other lengths to (and the gram is an arbitrary mass we use). So, the precise numbers are only meaningful as part of a system built on these units

"Since 2019 the metre has been defined as the length of the path travelled by light in vacuum during a time interval of 1/299792458 of a second, where the second is defined by a hyperfine transition frequency of caesium."

(https://en.m.wikipedia.org/wiki/Metre)

I wouldn't call it totally random, no. It's really derived from somethings real in this universe.

> So, the precise numbers are only meaningful as part of a system built on these units

That doesn't sound particularly random. And in fact we agree here.

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

#420

Post by importantstuff »

guenthert wrote: post #396
polskibus wrote: post #339

Earlier quoted context omitted.

Which answer on physicsexchange is the right one? The top scored ?

The top scored is just the answer liked best. The fact that it refers to proton decay and quantum gravity, both hypotheses which, as plausible as they might be, are not experimentally testable at this time, renders in my mind the confidence of the answer questionable.

The top answer has multiple reasons. The one I am referring to in particular is this section: "I should point out that if you believe that the standard model matter is complete, then anomaly cancellation requires that the charge of the proton is equal to the charge of the positron, because there is instanton mediated proton decay as discovered by t'Hooft, and this is something we might concievable soon observe in accelerators. So in order to make the charge of the proton slightly different from the electron, you can't modify parameters in the standard model, you need to add a heck of a lot of unobserved nearly massless fermions with tiny U(1) charge." It makes no reference to quantum gravity.
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