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Comment by akomtu | Hacker News Reader

Is it the shape of lithium's electron shell?

No. The 'faceting' of a crystal is determined by a minimization of the 'Gibbs free energy' [a thermo quantity determined mostly by the relative energies of different faces of the crystal, at low temp] over all the faces. The relative energies of the facets are in turn determined by the crystal structure, and the favored crystal structure is determined by the 'electronic structure' of the material itself. Li is an alkali atom, so presumably in the metal donates its outermost 's' electron to make a relatively simple metal. Almost never does crystal shape in any way reflect directly the atomic structure

It is the crystalline shape of pure lithium metal which is shown.

aren't shells just these vague clouds where an electron "might" be?

No.

Shells are rather precise representations of the wavelike properties of electrons as they exist bound in atoms.

Electrons are neither exactly waves or particles, they have properties of both.

If you try to interact with an electrons’ particle like properties you tend to get particles, when you try to inject with electrons’ wavelike properties you tend to get waves.

The dual nature can be hard to say just right and communicate.

The math of what’s going on describes it extremely well… the “this is what’s actually going on” descriptions are more like metaphorical stories because on a human scale quantum objects just don’t exist.

On this dual nature, can it be that the electron cloud is the electron itself? i.e. it's not a point-like particle that jumps around, but it's the probability function itself, that upon interaction with another cloud-particle may shrink into a tiny ball-like cloud, but never a point. In atoms, electrons interact in such a way that they assume curious drum-like shapes, but when they are set free somewhere in the interstellar space, the same electron will be a gigantic planet-size, albeit very thin, cloud. Edit: continuing this speculation, in the double-slit experiment an electron passes thru both slits, then shrinks into an atom-size cloud upon contact with the screen, and a "weak measurement" would be a way to slightly disturb the shape of the electron, to correspondingly disturb the shape of the detector.

The “reality” of any QM interpretation should be taken with a grain of salt and not too seriously. There is some debate, but yet what you’re proposing goes considerably too far. The dual nature is more or less real, you can’t distill it into one exact thing.

QED describes the behavior of electrons very well. Interpretations are projected from equations but what a thing “actually” is only comes from the models.

It can be hard to let go of wanting to come up with an intuitively satisfying explanation but there is not one. Your brain evolved in s world where experiences are classical not quantum. Unless you spend a ton of time interacting with quantum systems (and still maybe not) you’re not going to come up with an intuitively satisfying explanation of what an electron is.

The short answer is no.

There are experiments in which the electron does behave as a point-like particle (definitely smaller than anything that is currently measurable, if it has any size at all). In particular, any interaction always consumes or creates exactly one electron, there is never a half electron being affected (of course, it could be 2 or 3 etc electrons - but always a whole number, never a fraction). So, it doesn't behave like a cloud of something.

Secondly, there are experiments where it behaves like a wave in a field, showing self-interaction and peaks and troughs etc. This continues to happen even if you space it very far apart from other electrons. Experiments have been done using an electron cannon that can only fire one electron every hour or so at a double slit, and still you get the same diffusion pattern on the screen. So, the electron wave is still there and shows self-interference, even if you send it slowly. Clouds again don't have this type of behavior.

Not to mention, if the charge of an electron were distributed in a large cloud, that would have very measurable consequences for the electic and magnetic fields of that electron.

As others are pointing out, there is no way to think classically about quantum phenomena and still match all experiments.

What's the magnetic field of an electron in the double slit experiment before the electron has decided where it wants to be? The electron travels slowly, the detector screen may be very far, while the magnetic field travels fast.

In a sense you're right - it's not an electron that jumps around, the electron is its quantum amplitude wavefunction. Until you measure it, that is what you need to calculate the details of and time evolution of and interactions with.

And there can be electron wavefunctions that are macroscopically distributed for sure.

But as the electron's eventual interaction shape is a point, and never more than one point (even if the wavefunction was a large drumbell shape before!) we can't say that the electron "grows thinner and larger" itself, we have to conclude that there is a thing called a wavefunction (or quantum amplitude) that evolves that is not a point, that can be used to predict where/when the single-point "full electron" interaction with something else might take place.

A quantum weak measurement is a measurement where the object you want to study is allowed to interact with a part of the detector that doesn't immediately reduce everything to a single point interaction. As you correctly note, it does change the shape of the wavefunction, but what you also need to know is that the wavefunction change is not of the electron and the detector-part by themselves - there is a combined wavefunction for the electron + detector-part pair now, with a distribution of amplitudes for their possible states.

It quickly gets intuitively messy but this is the core...

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