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Forgive me for posting this idiotic question in advance since I have very little knowledge of physics, but I have often been confused about one thing recently.

Forgive me for posting this idiotic question in advance since I have very little knowledge of physics, but I have often been confused about one thing recently. From what I could gather a little isn't the whole electrons revolve in orbits thing proved false and outdated like universe is made of ether? I heard that even the iconic atom logo is all wrong since it is proved that electrons don't revolve around anything rather come in and out of existence and present themselves in probability clouds. If that is true then why do we still keep talking about shells and energy levels? Like I said my question may sound like a troll but I assure you it's not. Just want to know what's what.

acomar 6y ago
the orbitals aren't neat rings but there are definitely orbitals. they're shaped weirdly as they represent the space two electrons will probabilistically occupy. you can't pinpoint an electron and say it is precisely here in the orbital but there are fairly high odds that it's in the orbital.
- deleted 6y ago
  [deleted]
irjustin 6y ago
There are orbitals[0], but they're not so nicely circular like in that "atomic" atom that dominated from the 1950's. Each energy level has a different shape. Also, they don't 'orbit' like planets. It's now a probability space[1]. i.e. You will _likely_ find electrons in this 'orbital' somewhere, but could be anywhere.... but you have to go looking for them. Once you've found them, they're instantly somewhere else in a completely unknown area of that orbital. [0] https://en.wikipedia.org/wiki/Atomic_orbital https://en.wikipedia.org/wiki/Atomic_orbital [1] https://en.wikipedia.org/wiki/Atomic_orbital#Shapes_of_orbitals https://en.wikipedia.org/wiki/Atomic_orbital#Shapes_of_orbit...
- jiggawatts 6y ago
  > instantly somewhere else in a completely unknown area of that orbital. Mr Einstein may have a few words to say about that.
  - alblue 6y ago
    He would probably say “you are right; the Heisenberg uncertainty principle means that you cannot know both the electrons position and momentum exactly due to quantum uncertainty”
    - Viliam1234 6y ago
      I think the momentum is still limited by the speed of light.
      - MichaelBurge 6y ago
        So if you measured in succession fast enough, the particles would move continuously. So the probability density should be time-dependent.
        Viliam1234 6y ago
        Continuously, but always in a new unpredictable direction, i.e. Brownian motion. And I suppose if you keep measuring them fast enough, so much disturbance will kick them off the atom, so they are no longer in the shell. The shell is what happens when the electrons are left alone. (Not completely sure about this part.)
xvilka 6y ago
With QFT (Quantum Field Theory)[1] there are no particles at all - just perturbances of the corresponding fundamental fields. Moreover, seems like QFT is the dominant explanation to date. At least at the current level of understanding and according the fad. There is a problem with it - it's incompatible with the general relativity, so unlikely is completely true. But it explained so many phenomena. Some people think it's not even fundamental, nor the space, time, fields themselves - only geometry/topology is - see, for example, the amplituhedron[2][3]. While it doesn't represent our complex 3+1 dimensional reality, it's certainly a new way to look at things. Time will tell. [1] https://en.m.wikipedia.org/wiki/Quantum_field_theory https://en.m.wikipedia.org/wiki/Quantum_field_theory [2] https://en.m.wikipedia.org/wiki/Amplituhedron https://en.m.wikipedia.org/wiki/Amplituhedron [3] https://www.quantamagazine.org/physicists-discover-geometry-underlying-particle-physics-20130917/ https://www.quantamagazine.org/physicists-discover-geometry-...
- jiggawatts 6y ago
  Unless I'm missing something, the Amplituhedron is geometry over an abstract space and is just a clever way of simplifying calculations. Also, its proponents haven't yet been able to apply it to interactions that occur in our 3+1 spacetime, so far they've only applied it to toy models of physics. Clever algebra is not what the Universe "does", and you'll find that 99.9% of the geometry or topology topics in theoretical physics are over abstract, high-dimensional spaces that are a couple of steps removed from the ordinary goings on at the particle interaction level.
  - xvilka 6y ago
    Yes, I mentioned it doesn't describe our 3+1 dimensional reality. It's more than just the algebra/geometry though - it kills the locality and unitarity principles. So it has quite a few implications on how we think about underlying physics.
- vertbhrtn 6y ago
  I've seen a clever way to derive QM out of GR equations by making a single assumption: ds2exp(Cexp(-iwt)) = c2*dt2 - dx2 - dy2 - dz2. This extra exp() factor modulates the ds2 slightly, and when mixed with GR equations, it makes the time-dependent Schrodinger equation. Whether this math corresponds to any physics is a question, but if this idea is right, then the psi-function isn't some abstract "probabilities cloud", but rather a standing wave on top of the spacetime field governed by the GR equations.
pvg 6y ago
You might have missed it in the article since the word is close but the term is 'atomic orbital', in part because it's not an 'orbit'. The wikipedia page linked in one of the sibling comments covers the basic ideas without going too far off the detail deep-end.
madhadron 6y ago
You are correct, the Bohr model has been obsolete for almost a century. It continues to get trotted out because the more accurate model is quite unapproachable without a lot of math and study. When someone says "revolves around something" they are mentally projecting a whole sequences of measurements of the electron's position, one after another, that trace out a path. We are evolved to regard the path as a natural thing as opposed to focusing on the measurements. But we can't do that for electrons orbiting an atom, since measuring them involves wacking them with photons or something that bounce off in some direction so we can see that deflection. So all we get to talk about is the result of a measurement. When someone says "it's in this orbital," that's a statement about the values of energy and angular momentum a measurement will produce. What measurements actually produce those? Ones that involve absorbing or emitting photons, mostly, and we measure those by the energy of the photon absorbed or emitted, and those don't give us information about the position of the electron. You may think that we could put an electron into a very high orbit and then try to triangulate where it was when it emitted the photon based on the angle...but then you have to know where the atom is precisely, which means another measurement, which means some unknown momentum imparted, which means the energy spectrum of the photon we're trying to measure gets smeared... Meanwhile, if we measure position precisely, then we impart some new momentum vector to the electron. What the momentum vector would have been measured to be before that wasn't known, and so we have no idea how we have kicked it and the orbital (energy and angular momentum) can have various values if we measure them afterwards even if they would have always had a single value beforehand.
- yomly 6y ago
  I can't disagree with most of what you've said and it gives quite a classical intuition to the problem but it's still very classically grounded.
  - madhadron 6y ago
    You're right, it is, despite my care to only speak of the result of measurements, not properties of the state we measure.
- vertbhrtn 6y ago

acomar 6y ago

the orbitals aren't neat rings but there are definitely orbitals. they're shaped weirdly as they represent the space two electrons will probabilistically occupy. you can't pinpoint an electron and say it is precisely here in the orbital but there are fairly high odds that it's in the orbital.

deleted 6y ago
[deleted]

irjustin 6y ago

There are orbitals[0], but they're not so nicely circular like in that "atomic" atom that dominated from the 1950's. Each energy level has a different shape. Also, they don't 'orbit' like planets. It's now a probability space[1]. i.e. You will _likely_ find electrons in this 'orbital' somewhere, but could be anywhere.... but you have to go looking for them. Once you've found them, they're instantly somewhere else in a completely unknown area of that orbital. [0] https://en.wikipedia.org/wiki/Atomic_orbital https://en.wikipedia.org/wiki/Atomic_orbital [1] https://en.wikipedia.org/wiki/Atomic_orbital#Shapes_of_orbitals https://en.wikipedia.org/wiki/Atomic_orbital#Shapes_of_orbit...

jiggawatts 6y ago
> instantly somewhere else in a completely unknown area of that orbital. Mr Einstein may have a few words to say about that.
- alblue 6y ago
  He would probably say “you are right; the Heisenberg uncertainty principle means that you cannot know both the electrons position and momentum exactly due to quantum uncertainty”
  - Viliam1234 6y ago
    I think the momentum is still limited by the speed of light.
    - MichaelBurge 6y ago
      So if you measured in succession fast enough, the particles would move continuously. So the probability density should be time-dependent.
      - Viliam1234 6y ago
        Continuously, but always in a new unpredictable direction, i.e. Brownian motion. And I suppose if you keep measuring them fast enough, so much disturbance will kick them off the atom, so they are no longer in the shell. The shell is what happens when the electrons are left alone. (Not completely sure about this part.)

xvilka 6y ago

With QFT (Quantum Field Theory)[1] there are no particles at all - just perturbances of the corresponding fundamental fields. Moreover, seems like QFT is the dominant explanation to date. At least at the current level of understanding and according the fad. There is a problem with it - it's incompatible with the general relativity, so unlikely is completely true. But it explained so many phenomena. Some people think it's not even fundamental, nor the space, time, fields themselves - only geometry/topology is - see, for example, the amplituhedron[2][3]. While it doesn't represent our complex 3+1 dimensional reality, it's certainly a new way to look at things. Time will tell. [1] https://en.m.wikipedia.org/wiki/Quantum_field_theory https://en.m.wikipedia.org/wiki/Quantum_field_theory [2] https://en.m.wikipedia.org/wiki/Amplituhedron https://en.m.wikipedia.org/wiki/Amplituhedron [3] https://www.quantamagazine.org/physicists-discover-geometry-underlying-particle-physics-20130917/ https://www.quantamagazine.org/physicists-discover-geometry-...

jiggawatts 6y ago
Unless I'm missing something, the Amplituhedron is geometry over an abstract space and is just a clever way of simplifying calculations. Also, its proponents haven't yet been able to apply it to interactions that occur in our 3+1 spacetime, so far they've only applied it to toy models of physics. Clever algebra is not what the Universe "does", and you'll find that 99.9% of the geometry or topology topics in theoretical physics are over abstract, high-dimensional spaces that are a couple of steps removed from the ordinary goings on at the particle interaction level.
- xvilka 6y ago
  Yes, I mentioned it doesn't describe our 3+1 dimensional reality. It's more than just the algebra/geometry though - it kills the locality and unitarity principles. So it has quite a few implications on how we think about underlying physics.
vertbhrtn 6y ago
I've seen a clever way to derive QM out of GR equations by making a single assumption: ds2exp(Cexp(-iwt)) = c2*dt2 - dx2 - dy2 - dz2. This extra exp() factor modulates the ds2 slightly, and when mixed with GR equations, it makes the time-dependent Schrodinger equation. Whether this math corresponds to any physics is a question, but if this idea is right, then the psi-function isn't some abstract "probabilities cloud", but rather a standing wave on top of the spacetime field governed by the GR equations.

pvg 6y ago

You might have missed it in the article since the word is close but the term is 'atomic orbital', in part because it's not an 'orbit'. The wikipedia page linked in one of the sibling comments covers the basic ideas without going too far off the detail deep-end.

madhadron 6y ago

You are correct, the Bohr model has been obsolete for almost a century. It continues to get trotted out because the more accurate model is quite unapproachable without a lot of math and study. When someone says "revolves around something" they are mentally projecting a whole sequences of measurements of the electron's position, one after another, that trace out a path. We are evolved to regard the path as a natural thing as opposed to focusing on the measurements. But we can't do that for electrons orbiting an atom, since measuring them involves wacking them with photons or something that bounce off in some direction so we can see that deflection. So all we get to talk about is the result of a measurement. When someone says "it's in this orbital," that's a statement about the values of energy and angular momentum a measurement will produce. What measurements actually produce those? Ones that involve absorbing or emitting photons, mostly, and we measure those by the energy of the photon absorbed or emitted, and those don't give us information about the position of the electron. You may think that we could put an electron into a very high orbit and then try to triangulate where it was when it emitted the photon based on the angle...but then you have to know where the atom is precisely, which means another measurement, which means some unknown momentum imparted, which means the energy spectrum of the photon we're trying to measure gets smeared... Meanwhile, if we measure position precisely, then we impart some new momentum vector to the electron. What the momentum vector would have been measured to be before that wasn't known, and so we have no idea how we have kicked it and the orbital (energy and angular momentum) can have various values if we measure them afterwards even if they would have always had a single value beforehand.

yomly 6y ago
I can't disagree with most of what you've said and it gives quite a classical intuition to the problem but it's still very classically grounded.
- madhadron 6y ago
  You're right, it is, despite my care to only speak of the result of measurements, not properties of the state we measure.
vertbhrtn 6y ago