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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’

#421

Post by tinganho »

sullyj3 wrote: post #416
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?

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…

A thing can be explained with its constituent parts or explained by a parallel analogy. If you don't understand the constituent parts or the analogy or there are neither of these. You won't understand it.

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

#422

Post by exe34 »

aap_ wrote: post #26
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…

Charge is quantized. You cannot have just any amount of electric charge. An electron has three elementary units of negative charge, quarks have -1 and 2. Whether it's a coincidence that proton and electron charge are of the same magnitude (and the neutron is neutral) is another question, but at the elementary level you don't have that much choice for what the charge of a particle is.

Of course, the quarks had to go and be 1/3 or 2/3 of an e in charge. But they can never be observed isolated, so nature allows it.

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

#423

Post by DebtDeflation »

megmogandog wrote: post #302
timeagain wrote: post #268

Earlier quoted context omitted.

Ok here’s the problem. What hubris does it take to assume the fundamental constants could be changed? Just because they appear in math equations doesn’t mean they can be twiddled and tweaked like programming variables. We have no prior knowledge or justification to believe any constants have been “tuned”, because we have no justification in suggesting other possible values. We could just as easily say that life on ea…

I think I could've phrased my comment better. I'm not assuming the constants can be changed; axiomatically, they cannot, because they're fundamental constants of the universe. I'm also not assuming that some agent was around to do the tuning. In its basic form 'fine tuning' just means that if one of the values were even slightly different we wouldn't have anything like the universe we see today, including life. The v…

>because they're fundamental constants of the universe

They're constants but are they fundamental? There are a lot (19?) of free parameters in the Standard Model. We determine them experimentally. But that doesn't mean that there isn't some deeper explanation that results in those values. We just don't know what it is yet.

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

#424

Post by exe34 »

ajkjk wrote: post #308
alex_smart wrote: post #286

Earlier quoted context omitted.

https://youtu.be/36GT2zI8lVA Richard Feynman on why questions

That video really annoys me. He's right at one level but totally wrong at another. Yes, you have to explain everything in terms of things people can understand and if they don't know much you can't give a correct explanation... but also, if you actually try, people can understand a lot more than he's pretending they can. Not at a technical level, yeah, but intuitively, it is possible to get general understandings way…

> Not at a technical level, yeah, but intuitively, it is possible to get general understandings way beyond his attempts at answering that question.

The issue with giving people an intuitive model that's not at the same level of complexity to the mathematical models, in my experience, is that a lot of people, including out-of-field experts then run with the intuitive model into bizarre territory and treat it as a prediction of the original tested theory. They reason correctly within the simplified world of the analogy but when it clashes with the real world, they dig down and reaffirm their preconceived notions.

On the other hand, I suppose they were never going to honour Cromwell's rule anyway, so maybe it doesn't matter.

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

#425

Post by da39a3ee »

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…

Maybe that was a form of matter that was stable early in the history of time and matter, and so it survived, but others didn't?

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

#426

Post by pnut »

oldandtired wrote: post #312
nojvek wrote: post #238

Earlier quoted context omitted.

It’s essentially asking why is the speed of light 299,798,452 m/s or the gravitational constant 6.67x10-11 Nm2/kg2 I’m sure a universe could work with those constants varied but that’s the one we have in our universe. There could be hypothetical universes with protons being half of electron and atoms would have twice the protons. However the fundamental constants are just that. A number that allows us to reason about…

The first thing to point out here is that the > the speed of light is not > 299,798,452 m/s It is quite inaccurate to say this. The correct way to phrase this is that the speed of light is 1/sqrt(permeability * permittivity) of the medium through which the light is traveling. For a perfect vacuum, these two properties of that vacuum give a result as specified above. For other specified medium, you will get a differen…

Another important point is that other things besides light (for instance, gravitational influence) travel at the speed of light.

It's actually the speed of causality / information transfer.

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

#427

Post by kjqgqkejbfefn »

megmogandog wrote: post #255
timeagain wrote: post #210

Earlier quoted context omitted.

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

Which fine tuning arguments are you referring to? As I understand it, 'fine tuning' is simply a fact of the universe: that the fundamental constants have values that allow for the emergence of complexity, and that even slight changes to those values would lead to homogeneous and featureless universe. I don't have the physics background to demonstrate this for myself, but I believe it. To then reason from that fact to…

>doesn't invalidate the appearance that the fundamental constants of the universe were fine tuned for the production of complexity/life.

I think it's the other way around, it's because we are complex reasoning forms of life that we must observe fine tuning of physical constants, necessary for the emergence of complexity.

See: https://en.wikipedia.org/wiki/Anthropic_Bias

I also came up with my own variation of the anthropic principle:

- 1. Extend the anthropic principle beyond physical connstant. Include factors such as the goldilock zone from planetology, the symbiogenetic origin of eukaryotic cells, the presence of the moon, etc ...

- 2. Rethink the "anthropic situation" as a collection of coincidences. It doesn't directly "select for" observers, but for the right coincidences that allow them to exists.

Two paths open for us from here:

- 3.1. Either God (or whatever phenomenon can explain the presence of the right coincidences) exists and we were dealt with the right set of coincidences.

- 3.2. Or alternatively, this collection of coincidences was built up by a random sampling process. If this is the case, then we should expect this collection to contain *superfluous* coincidences that have no impact on the existence of observers. Imagine you lost the key to your house and someone cuts a key at random from a bit of metal, which luckily turns out to unlock your door. This key has more chances to feature superfluous, redundant notches, than to be an exact copy of the original key.

----

This brings a counterpoint to the cognitive perspective on pattern recognition and could be used to challenge or refine our understanding of why we perceive certain phenomena as 'coincidences' (for instance why the Moon/Sun ratios are the same for both their diameters and distances to the Earth, which allows us to observe quasi-perfect eclipses). This superfluous anthropic principle, in this case, suggests that these perceived coincidences might have an actual basis in the physical properties and probabilistic events of the universe. In other words, it is because God doesn't exist that we can see 'meaningful' coincidences "hinting" at its existence (from the perspective of magical thought).

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

#428

Post by Gravityloss »

exmadscientist wrote: post #189
Gravityloss wrote: post #132

Earlier quoted context omitted.

There exist "stable" exotic particles of that have non ordinary amounts of lower level quarks. https://www.symmetrymagazine.org/article/lhcb-discovers-long... Maybe they might have non integer charge.

In QCD, they cannot. All Feynman diagram vertices involved in producing these things (in fact all QCD vertices period) only deal in integer charge units and never leave fractional charges floating around.

Ok, I see. Also pentaquarks all have integer charge.

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

#429

Post by photon_lines »

TheOtherHobbes wrote: post #96
aap_ wrote: post #26

Earlier quoted context omitted.

Charge is quantized. You cannot have just any amount of electric charge. An electron has three elementary units of negative charge, quarks have -1 and 2. Whether it's a coincidence that proton and electron charge are of the same magnitude (and the neutron is neutral) is another question, but at the elementary level you don't have that much choice for what the charge of a particle is.

But why is charge quantised? In the Standard Model properties are defined as relationships within/between symmetry groups. There are only so many things you can do to/with/in a symmetry group, and that's where the quantisation comes from. But... that's a mathematical metaphor applied to observations. It's a good fit, but it doesn't explain why it's those symmetry groups and not others, or why symmetry groups are a go…

Information compression (edit sorry you said no one knows why the need to symmetry groups and I provided the answer).

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

#430

Post by nurettin »

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 think we simply observe the most stable states of existence which preclude asymmetry and all other states of matter have either gone extinct, or are so fickle that we can only observe them momentarily. So the deep truth behind why and what exists and what cannot is pretty straightforward.
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