Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

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

quantamagazine.org

Post reply on HN
Print view View original

391–400 of 591 posts

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

#391

Post by kalekold »

dcow wrote: post #331

“The proton is a quantum mechanical object that exists as a haze of probabilities until an experiment forces it to take a concrete form.” I’m getting really tired of hazy probability distributions and waves that only collapse and materialize when observed. I 100% accept that QM is a useful tool to model our current understanding based on increasingly sophisticated observations, but I fundamentally don’t believe that…

> I still have bets on this all being a massive game of life.

You might be right!

https://writings.stephenwolfram.com/2020/04/finally-we-may-h...

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

#392

Post by jacquesm »

wombatpm wrote: post #279
DiscourseFan wrote: post #145

Earlier quoted context omitted.

I'm getting very strong "angels on a pinhead" vibes from this

Measure the area of a pinhead, divide by cross-sectional area of an angel. Easy peasy.

Division by zero error.

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

#393

Post by okamiueru »

stevenhuang wrote: post #386
okamiueru wrote: post #379

Earlier quoted context omitted.

I'm not convinced. When he talks about things I understand, he does so in a way that I still find frustratingly convoluted. In these cases, it's not for a lack of education. It probably just means that this style of presenting topics just isn't for me, which is completely fine. Diversity in free education is great and commendable. But I think you touch on the part that I think is the reason why. Because PBS tries to…

Yeah, your confusion there is like being confused from the use of a literary device. The intent was exactly to illustrate why the implication 'life -> multiverse' may be problematic. It was communicated just fine, I think you should continue watching?

Are you sure you got the argument I'm presenting? You did quickly make an edit to avoid a rather rude remark.

My point is that their use of literary devices, as you put it, are often misleading if not flat out wrong. The listener needs to he able identify them as such, and I don't think that's a good way to communicate science.

It doesn't mean that PBS is bad. Note that I have made no such statement. I'm just saying that I dislike it, and tried to be constructive as to why. If this offended you, like your initial remark might suggest, perhaps you are reading too much into it.

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

#394

Post by bbor »

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?

“The model does not hold” === “existence wouldn’t be possible”. We found atomic particles, then did some more experiments and found quarks within the atomic particles. The quarks appear to be complex but predictable subsets of the particles. So “why do those subsets add to 1” invites a tautology, because the whole reason we found them in the first place is that they add up to exactly one, and therefor can be part of atoms.

It’s like asking why the left engine of an aircraft happens to emit the same amount of thrust as the right engine; if that wasn’t the case, there wouldn’t be a plane to talk about in the first place, just an art piece or a flaming crash.

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

#395

Post by aleph_minus_one »

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?

> What causes it? Consistency of a model cannot be the ultimate reason, right?

Which epistemic foundation in which your "why" question is answered do you consider as acceptable for you?

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

#396

Post by guenthert »

polskibus wrote: post #339
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…

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.

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

#397

Post by coldtea »

foldr wrote: post #382
chaxor wrote: post #366

Earlier quoted context omitted.

I just would like to point out that "why" is not a scientific question. Feynman mentions this quite a lot. The question "why" doesn't have answers in science. A question of "How" has a better chance of being answered in science.

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 leads to a theoretical derivation of the mysterious mass ratios of quarks and the charged leptons. Quantum gravity is quantisation not only of the gravitational field, but also of the point structure of space-time."

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

#398

Post by stevenhuang »

okamiueru wrote: post #393
stevenhuang wrote: post #386

Earlier quoted context omitted.

Yeah, your confusion there is like being confused from the use of a literary device. The intent was exactly to illustrate why the implication 'life -> multiverse' may be problematic. It was communicated just fine, I think you should continue watching?

Are you sure you got the argument I'm presenting? You did quickly make an edit to avoid a rather rude remark. My point is that their use of literary devices, as you put it, are often misleading if not flat out wrong. The listener needs to he able identify them as such, and I don't think that's a good way to communicate science. It doesn't mean that PBS is bad. Note that I have made no such statement. I'm just saying…

I did want to avoid implying that videos are harder to understand if you find nonverbal cues hard to understand, but sure. That would genuinely be a reason to avoid PBS videos and that's fine.

The point is their use of the literary device here was not misleading nor 'flat wrong'. It is serving as a jumping off point from the video title 'Does Life Need a Multiverse to Exist?'. You may argue that such a question is ill posed, but then state your argument properly.

Read: they are NOT talking about the anthropic principle here. You are probably confused because you are trying to shoehorn this into discussion when the video is not even talking about this yet. Yes the anthropic principle is cogent to the video but not until later.

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

#399

Post by [deleted] »

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"

[deleted]

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

#400

Post by XorNot »

hansbo wrote: post #372
XorNot wrote: post #363

Earlier quoted context omitted.

Isn't the primary experimental argument beta decay from that link? A nucleus can emit a positron, and observably loses nuclear charge equal to one positive electron. So by a pretty simple inferrence you could conclude the proton has a positive in it, hence the charge (it of course isn't literally like this for other reasons though). And since we also observe antiprotons, the opposite can clearly apply.

So a proton can emit a positron. Does that mean that the positron is somehow "part" of the proton? Does it mean that their wave functions interact in some specific way? Is there another reason? Quantum physics has always bothered me, personally, since I find it difficult to understand reasons. Not philosophical reasons, I am fine with axioms and foundations to models, but rather intuitive reasons why it works a certa…

Sort of? But it's less "there is a particle doing things" and more "there's a probability field which can describe a particle doing something" (alongside a bunch of other probabilities it interacts with).

One of the ways you can calculate the probability of nuclear decay for example is to assume that the particle you expect to see is literally existent and trapped inside a potential well defined by the atomic nucleus and then calculate the probability it tunnels out of that to free space.

The thing is "why" does get pretty anthropic: protons match electrons because we observe them to, and then on top of that we observe nuclear decay causing the conversion of a proton to a neutron + a positron (within the limits of our instruments) - so our model predicts that these are in fact the same value, and we keep measuring to check that they converge in that direction (it would be a big deal, for example, if we discovered this wasn't the case - every physicist would love to find out that proton charge and electron charge are actually slightly different).

Post reply on HN