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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’

#91

Post by JumpCrisscross »

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…

> why must protons and electrons be perfectly complementary regarding charge?

According to QED's spin origin of charge, it's because charge comes from spin. What values a particle's spin can take are restricted to certain integer or half-integer values.

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

#92

Post by [deleted] »

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…

[deleted]

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

#93

Post by selecsosi »

derefr wrote: post #82
yifanl wrote: post #76

Earlier quoted context omitted.

How would we ever distinguish what half-a-proton is in a universe where all protons ever are _always_ paired off?

Presumably the same way we distinguish individual quarks: by smashing the atoms up. (The more interesting question would be the opposite: what if it was two electrons per proton? Then you could throw around some photons and end up with a half-proton negatively-ionized molecule. What would that look like?)

You are going down the path of theoretical particle physics! It is the ultimate question of that to answer what is the fundamental element that makes up matter and what should we "name" that has a useful property that can either be used or helps to explain how other things work.

In reality, "protons" do not "exist" but are semi(very) stable collections of energy that interact in an interesting enough way in a group that it is useful for us to retain the name, rather than refer to it by its constituents.

Electrons don't really glob up into things like atoms due to repulsion (no moderation by the stron/weak nuclear forces) so we don't have a really useful reason to keep going beyond the definition of the electron so we just stop trying to find additional constituent parts.

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

#94

Post by jiggawatts »

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

Quantum mechanics is a religion with mathematics instead of just holy texts.

Several studies have been done into whether practicing theoretical physicists using QM in their everyday work agree on the most basic tenets of the field.

Spoiler: they disagree on every aspect while simultaneously assuming that their opinions are correct and that everyone else agrees with them.

That’s how religions work, not how science does. Factions instead of consensus. Branches splitting off all the time and never supplanting the majority. Orthodoxy (Copenhagen). Shunning anyone that steps out of line (Everett). Refusing to question the holy texts, etc…

Another key symptom is requiring members to prove their devotion by saying and doing things that are obvious nonsense. Bending their common sense to the will of the group. In Christianity this is the trinity: one God that is three. In QM it’s the wave-particle duality, which is just nonsense. You can’t have a point with a kilometre long wavelength!! Yet, we are to believe (on faith!) that radio waves are made of photons.

Turns out that magical thinking and religiosity is the essential nature of humans, especially in large groups.

Whenever there is insufficient evidence to bring everyone into line, the line splinters into warring factions where the best argument each tribe has is: “my tribal leader said so!”

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

#95

Post by a_gnostic »

wiml wrote: post #40
lIl-IIIl wrote: post #28

Earlier quoted context omitted.

There's also a anti-proton which has a negative charge. I think this is probably the smallest charge there is. A neutron can decay into a proton, electron, and anti-neutrino. So maybe one way to think of it is that a proton is a neutron that is missing an electron, that's why it has the opposite charge of the electron.

The quarks that make up a proton (or neutron, etc) have charges that are multiples of 1/3 the electron charge. So in one sense that is the real unit charge. But because as far as we know quarks can never exist in isolation we can only ever see particles with multiples of the electronic charge.

The number assigned to charge is an arbitrary convention. You could assign quarks with full numbered charges, instead of fractions, but you'd have to rework and recalculate all of physics and chemistry to get the new values right, and that's just too much work.

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

#96

Post by TheOtherHobbes »

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.

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 good fit at all.

There's likely some kind of fundamental mechanism that generates these symmetries, and no one knows what that is.

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

#97

Post by I_Am_Nous »

jononomo wrote: post #67
calibas wrote: post #34

Reductionist philosophy is very common in science. It's essentially the idea that you can break things down into simpler parts to better understand how everything works. It's kind of "common sense", if you understand how all the components on a circuit board function individually, then you can piece together how the entire board will function. In computer science, you can reduce everything to operations comparing 1s…

> the more we learn, the more we realize how much we don't know This is why the "god of the gaps" critique is so short-sighted. It relies on the assumption that as science progresses it will "close the gaps". In reality the opposite happens. Another example is the cell -- in Darwin's day it was thought to be a simple thing, but then we learned more about it and it turned out to be monstrously complex and the mystery…

We have kind of an opposite problem to the god of the gaps as well, in which a phenomenon can be determined to "just be the way it is", such as objects with mass exerting gravitational forces on each other. We can say "God made them do that" or we can give up and say "We'll never know why, it's just a constant" and both are equally problematic because either way, we assume we can't eventually discover the "why".

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

#98

Post by NegativeLatency »

bugbuddy wrote: post #73
femto wrote: post #64

Earlier quoted context omitted.

In the same vein, a neutron can decay into a proton, an electron and a neutrino (Beta decay), so in some sense the neutral neutron is the combination of an electron and proton. (A connection is there?) In a simplistic way, I see a neutron star as just being a lump of regular (atomic) matter where the high pressure has forced all the electrons into the protons. Question for someone who might know: Was pressure so high…

I also have a question. Why should any theoretical predictions be regarded as Science if there is no feasible way to test them?

I think you might need to define your terms more specifically/clearly to be able to get an answer to this.

There's always the layman vs scientists definition of true. Like I think most people would say we know gravity exists, but in actuality we don't really know what gravity is, but we can measure how objects behave and make useful predictions about our world and universe because of that, with it lining up with other stuff we think we know.

Sorta similarly there's the scientific definition of something like dark matter/dark energy where there useful for modeling stuff but unlike what the general public thinks nobody has actually been able to point to a physical object that is dark matter to my knowledge, it's dark because it's unseen, not because it's like chunks of black stuff we can't see.

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