Understanding the probability cloud?

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Discussion Overview

The discussion revolves around the concept of the probability cloud of electrons in atoms, particularly in relation to the classical Bohr model of the atom. Participants explore the implications of observing an electron and the nature of its behavior within quantum mechanics (QM).

Discussion Character

  • Exploratory
  • Debate/contested
  • Conceptual clarification

Main Points Raised

  • One participant questions whether an electron could be observed to orbit in a defined manner from its own perspective, despite the traditional view that it exists in a probability cloud.
  • Another participant argues that the concepts of "appearance" and "perspective" do not apply to electrons in the same way they do to macroscopic objects, emphasizing the differences in behavior at the quantum level.
  • A later reply suggests that while imagining an observer on an electron is possible, the more pertinent question is about the nature of electrons and what "orbiting" means in quantum mechanics.
  • One participant notes that the probability cloud is a visualization derived from the wave-function, which is part of various interpretations of quantum mechanics.
  • Another participant recommends studying quantum mechanics from reputable texts to better understand these concepts.

Areas of Agreement / Disagreement

Participants express differing views on the applicability of classical concepts like "orbiting" to quantum particles, and there is no consensus on the interpretation of the probability cloud or the nature of observation in quantum mechanics.

Contextual Notes

Participants highlight limitations in understanding the implications of quantum mechanics, particularly regarding the relationship between theoretical models and observable phenomena. There is also mention of the need for further study to grasp these complex ideas.

Doomsday92
I understand that the concept of a atom resembling a solar system is disregarded as being untrue because this is based on the Bohr model which doesn't represent how an electron would actually appear in its probability cloud. However, would it be possible that if there were an observer on the electron that From it's observable plane it might orbit on a given plane from its perspective given how bizarre things get at the quantum level?

From a regular Joe with just a tenuous grasp on the mere basics.
 
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Doomsday92 said:
However, would it be possible that if there were an observer on the electron that From it's observable plane it might orbit on a given plane from its perspective given how bizarre things get at the quantum level?
Not possible.

You threw those words "actually appear" and "perspective" out there, but you need to think a bit more about what they might mean in this context. Macroscopic things have an actual appearance: light reflected from the object forms and image on the retinas of our eyes, a piece of photographic film, the array of photosensors inside a digital camera, whatever we're using to form the image, we look at the image, and we say that that's how the object "appears". But we can't reflect light off of an electron; all we can do is send a photon in the general vicinty of the atom, and every once in a while it comes out a different angle than we went in. Nor can we attach a piece of photographic film or an array of photosensors to the electron to come up with the "perspective" of an observer on the electron.

So we don't have any sensible notion of "appearance" or "perspective". However, that doesn't mean that things are bizarre at the quantum level, it means that they're different. Let go of the idea that very small things are like the macroscopic objects that surround us, except smaller and harder to study, and then you can start understanding the different but not bizarre rules that govern their behavior.
 
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Thanks for the reply Nugatory. I didn't mean to say that we would be the observer of the electron with some instrument. Let's say that an atom does behave like a mini solar system, and on an electron there was an observer. Would he observe the electron as orbiting on a set axis within his observable plane or would he see his "planet" appearing randomly in its probability cloud.
 
Nugatory said:
Not possible.

You threw those words "actually appear" and "perspective" out there, but you need to think a bit more about what they might mean in this context. Macroscopic things have an actual appearance: light reflected from the object forms and image on the retinas of our eyes, a piece of photographic film, the array of photosensors inside a digital camera, whatever we're using to form the image, we look at the image, and we say that that's how the object "appears". But we can't reflect light off of an electron; all we can do is send a photon in the general vicinty of the atom, and every once in a while it comes out a different angle than we went in. Nor can we attach a piece of photographic film or an array of photosensors to the electron to come up with the "perspective" of an observer on the electron.

So we don't have any sensible notion of "appearance" or "perspective". However, that doesn't mean that things are bizarre at the quantum level, it means that they're different. Let go of the idea that very small things are like the macroscopic objects that surround us, except smaller and harder to study, and then you can start understanding the different but not bizarre rules that govern their behavior.
Hmm...

We employ frame transformations all the time in particle physics. So we can imagine putting an "observer" on an electron -- or even the electron as the observer of its surroundings. It doesn't matter what frame of reference we use to solve Schrödinger's equation. So the problem I see with the OP's suggestion is not imagining an observer on the electron, but addressing the more interesting question of what an electron, a nucleus, or an atom are and what "orbiting" means in QM. Those are the questions our "regular Joe" needs to look into and he can't do that without studying QM.
 
Doomsday92 said:
Thanks for the reply Nugatory. I didn't mean to say that we would be the observer of the electron with some instrument. Let's say that an atom does behave like a mini solar system, and on an electron there was an observer. Would he observe the electron as orbiting on a set axis within his observable plane or would he see his "planet" appearing randomly in its probability cloud.

QM is a theory about observations that appear here in the macro world. Whats going on in between the theory is silent about. Since ts not part off the macro world what you suggest the theory says nothing.

This 'cloud' is simply visualization of the calculation of those probabilities from what's called the wave-function. It's part of interpretations what the wave-function means. You can look them up if interested, but personally I wouldn't worry until you have studied some properer QM from a good text.

Two start with for beginners I like Susskind's books:
https://www.amazon.com/dp/0465075681/?tag=pfamazon01-20
https://www.amazon.com/dp/B06XC7F6QG/?tag=pfamazon01-20

Thanks
Bill
 
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