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I don't know much about physics (I am trying to learn more), but does anyone else find the idea that the universe is made of "little balls" fundamentally wrong?

I don't know much about physics (I am trying to learn more), but does anyone else find the idea that the universe is made of "little balls" fundamentally wrong? It just feels like it will never end. First, we thought that atom is fundamental. Then electrons, protons and neutrons were discovered. Then, we discovered that there are smaller particles. Are we ever going to discover a fundamental particle that cannot be broken up? What would it be made of? How much space would it take up? Just some armchair philosophy.

shadowofneptune 6y ago
It gets worse when you consider that they are also equally valid as waves.
kosh2 6y ago
I would say it is filled with not made out of. The emptiness of space is not made out of particles.
- pixl97 6y ago
  The emptiness of space is filled with fields.
  - kosh2 6y ago
    Yes. But as far as I know, space itself is not made out of particles.
    - pixl97 6y ago
      This depends what you think about virtual particles and quantum foam.
vesinisa 6y ago
Do not think about "little balls". It's a fundamentally broken mental image that everyone was taught in high school chemistry. Already at atomic level things are adequedly expressed only as wave functions. Matter is not little balls made up of even tinier balls, but something altogether stranger - recall that matter and energy are interchangeable. I like to imagine the subatomic particles (like neutrons and protons) as beautiful rays of energy only temporarily trapped in particle form as ugly matter.
humanistbot 6y ago
Step one in learning subatomic physics is to completely disregard your intuitions about what feels right or what seems to make sense.
davrosthedalek 6y ago
As far as we know, leptons are not composite. They might be able to decay, but a muon or electron is fundamental. It's not made up from something else. Quarks seem to be fundamental too. Same for photons. We are pretty confident of this, because the theory describing them is so precise -- QED is the best tested theory of all, to about 14 digits IIRC. In fact, a big factor in the discovery that a proton is a composite system was that it could not be described by QED, it has a anomalous magnetic moment.
- endisneigh 6y ago
  I know nothing of physics, but I'm just curious - could you explain in layman's terms how one could say an electron is fundamental without infinitely precise measurement tools?
  - whatshisface 6y ago
    You can't. It's a universal philosophical limitation on science. One humorous way to phrase it would be, "there could always be a gnome hiding behind the camera." You have got to see the implicit, unspoken qualifiers that are on all statements like that. "It would be counter to all known patterns if...", "it would have to be extraordinarily small, beyond unimaginable sensitivities, if..." and "we can't imagine any practical distinction between what it seems like and what it might be," are all reasonable interpretations of the statement "it isn't." The only unreasonable interpretation would be the literal one. (P.S. It is not actually fundamental, it is made up of right-electrons and left-electrons, coupled together.)
  - gus_massa 6y ago
    100% sure is not possible, but there is some good circumstantial reasons. Let's use the bad model that an electron is a small ball made of some magic material. And that the material inside it is even, there are not more dense parts. Also the charge is distributed evenly, it's not concentrated in some parts. The electron is spinning, so you imagine that the ball is spinning. So you can calculate the angular momentum of the electron, assuming it's an even ball of a magical material. The angular momentum can be measured experimentally, so you can calculate how fast the electron is spinning, assuming it's an even ball of a magical material. It has charge, and the charge is moving, so it is like a small magnet. You have calculated how fast it is spinning, and you can calculate the magnetic moment of the electron, assuming it's an even ball of a magical material. Now you go to the lab and measure the real magnetic moment of the electron and it is twice the value of the number you got assuming it's an even ball of a magical material. This number is called g, so for an electron g=2 (actually almost 2). You can repeat the same calculation for protons, and the g of the proton is g~=1.410606... For an elementary particle, there are theoretical reasons to be sure that g=2. So the conclusion is that the electron is an elementary particle and the proton is a composite particle. --- Bonus: Actually, you can get a perfectly isolated electron alone, because there are nasty virtual particles floating around. You can't see the virtual particles, but they cause small corrections in the experiments with high energy particles. In particular, the g of the electron is not exactly 2 because these virtual particles cause a small correction. The value is approximately g=2.00231930436182(52) https://en.wikipedia.org/wiki/Electron_magnetic_moment https://en.wikipedia.org/wiki/Electron_magnetic_moment If it smell to much hand waving, don't worry. There are very good models for all the nasty virtual particles, and you can make a long calculation of the effect of them, and calculate these correction. You can make the theoretical calculation and the experimental measure and they agree with 10 significant figures. They prefer to publish a=(g-2)/2 and a_thoretical = 0.001159652181643(764) a_experimental = 0.00115965218073(28) So the model of a electron as an elementary particle with some virtual particles floating around is quite accurate.

shadowofneptune 6y ago

It gets worse when you consider that they are also equally valid as waves.

kosh2 6y ago

I would say it is filled with not made out of. The emptiness of space is not made out of particles.

pixl97 6y ago
The emptiness of space is filled with fields.
- kosh2 6y ago
  Yes. But as far as I know, space itself is not made out of particles.
  - pixl97 6y ago
    This depends what you think about virtual particles and quantum foam.

vesinisa 6y ago

Do not think about "little balls". It's a fundamentally broken mental image that everyone was taught in high school chemistry. Already at atomic level things are adequedly expressed only as wave functions. Matter is not little balls made up of even tinier balls, but something altogether stranger - recall that matter and energy are interchangeable. I like to imagine the subatomic particles (like neutrons and protons) as beautiful rays of energy only temporarily trapped in particle form as ugly matter.

humanistbot 6y ago

Step one in learning subatomic physics is to completely disregard your intuitions about what feels right or what seems to make sense.

davrosthedalek 6y ago

As far as we know, leptons are not composite. They might be able to decay, but a muon or electron is fundamental. It's not made up from something else. Quarks seem to be fundamental too. Same for photons. We are pretty confident of this, because the theory describing them is so precise -- QED is the best tested theory of all, to about 14 digits IIRC. In fact, a big factor in the discovery that a proton is a composite system was that it could not be described by QED, it has a anomalous magnetic moment.

endisneigh 6y ago
I know nothing of physics, but I'm just curious - could you explain in layman's terms how one could say an electron is fundamental without infinitely precise measurement tools?
- whatshisface 6y ago
  You can't. It's a universal philosophical limitation on science. One humorous way to phrase it would be, "there could always be a gnome hiding behind the camera." You have got to see the implicit, unspoken qualifiers that are on all statements like that. "It would be counter to all known patterns if...", "it would have to be extraordinarily small, beyond unimaginable sensitivities, if..." and "we can't imagine any practical distinction between what it seems like and what it might be," are all reasonable interpretations of the statement "it isn't." The only unreasonable interpretation would be the literal one. (P.S. It is not actually fundamental, it is made up of right-electrons and left-electrons, coupled together.)
- gus_massa 6y ago
  100% sure is not possible, but there is some good circumstantial reasons. Let's use the bad model that an electron is a small ball made of some magic material. And that the material inside it is even, there are not more dense parts. Also the charge is distributed evenly, it's not concentrated in some parts. The electron is spinning, so you imagine that the ball is spinning. So you can calculate the angular momentum of the electron, assuming it's an even ball of a magical material. The angular momentum can be measured experimentally, so you can calculate how fast the electron is spinning, assuming it's an even ball of a magical material. It has charge, and the charge is moving, so it is like a small magnet. You have calculated how fast it is spinning, and you can calculate the magnetic moment of the electron, assuming it's an even ball of a magical material. Now you go to the lab and measure the real magnetic moment of the electron and it is twice the value of the number you got assuming it's an even ball of a magical material. This number is called g, so for an electron g=2 (actually almost 2). You can repeat the same calculation for protons, and the g of the proton is g~=1.410606... For an elementary particle, there are theoretical reasons to be sure that g=2. So the conclusion is that the electron is an elementary particle and the proton is a composite particle. --- Bonus: Actually, you can get a perfectly isolated electron alone, because there are nasty virtual particles floating around. You can't see the virtual particles, but they cause small corrections in the experiments with high energy particles. In particular, the g of the electron is not exactly 2 because these virtual particles cause a small correction. The value is approximately g=2.00231930436182(52) https://en.wikipedia.org/wiki/Electron_magnetic_moment https://en.wikipedia.org/wiki/Electron_magnetic_moment If it smell to much hand waving, don't worry. There are very good models for all the nasty virtual particles, and you can make a long calculation of the effect of them, and calculate these correction. You can make the theoretical calculation and the experimental measure and they agree with 10 significant figures. They prefer to publish a=(g-2)/2 and a_thoretical = 0.001159652181643(764) a_experimental = 0.00115965218073(28) So the model of a electron as an elementary particle with some virtual particles floating around is quite accurate.