2
$\begingroup$

I understand that electrons do not orbit the nucleus, instead they have a higher probability to be found at some specific regions.

But what makes they appear more frequently in the orbital regions? There are equations (like Schrödinger) that are able to describe this wave function, but what causes it?

$\endgroup$
12
  • $\begingroup$ If your question is essentially "why are some things quantised", the answer is we have no idea, that's just things seem to be. $\endgroup$ – Charlie Jul 27 '20 at 18:36
  • $\begingroup$ Are you asking why the probability density is shaped this way? Or are you asking what causes quantization? To the latter there is no known answer. $\endgroup$ – AlmostClueless Jul 27 '20 at 18:38
  • 1
    $\begingroup$ A pedantic point that might be useful at some future time: electrons don't have energy levels. Atoms do, and molecules do, and nuclei do, and solids do, ... $\endgroup$ – garyp Jul 28 '20 at 1:07
  • 1
    $\begingroup$ Isnt this because waves about a nucleus only have whole number frequency solutions in order to be stable/not destructively interfere? And those frequencies tell you the energies. $\endgroup$ – J Kusin Jul 28 '20 at 17:17
  • 1
    $\begingroup$ @rafaelcastrocouto I am not certain but ive heard that explanation, maybe it will help your searching. If you picture bending a 2D wave around a circle, if the peaks dont line up from successive windings, they will destructively interfere. So only certain frequencies are stable, and frequency is tied to energy levels. Something analogous $\endgroup$ – J Kusin Jul 29 '20 at 14:43
4
$\begingroup$

Nobody knows the answer. All we know is that quantum mechanics is in perfect agreement with experiment. All you can do is to critically investigate any intuitive concepts that you may have that are incompatible with quantum mechanics.

$\endgroup$
2
$\begingroup$

I believe that when Richard Feynman was asked what the Schrödinger equation (SE) was, he replied (paraphrasing from memory): 'it's something that happened in Schrödinger's mind!'

In truth we don't know why the SE works, only that it does tremendously well!

I understand that electrons do not orbit the nucleus, instead they have a higher probability to be found at some specific regions.

The SE is a second order, linear partial differential equation and quite similar to other important equations like the (Classical) wave equation, diffusion equation and Fourier heat equation.

Like the SE, when these equations act on a bounded domain they become eigenvalue/eigenfunction problems. In Quantum Mechanics we call this quantisation.

In the case of the SE, the bounded wave functions (solutions to the SE) combined with the Born rule this yields the probability density distributions which tend to be wave-like.

$\endgroup$
2
$\begingroup$

The energy levels of the Hydrogen atom have specific energy levels because the solution of the S-equation says so. Other than this no one knows why things are described by the S-eqn. It just the way things are. The S-eqn provides a mathematical explanation of the way things work. It has been checked against known results and it agrees perfectly so there is little reason to doubt it.

$\endgroup$

Not the answer you're looking for? Browse other questions tagged or ask your own question.