• Question: Why don't electrons not spin into the centre of a nucleus? Currently I'm only aware of the cloud analogy of electrons around a nucleus, which doesn't seem to explain this phenomenon.

    Asked by sebstrug to Ben, Clare, Ezzy, Mario, Sam on 16 Mar 2012.
    • Photo: Mario Campanelli

      Mario Campanelli answered on 15 Mar 2012:

      very deep question, that has lead to the development of quantum mechanics.
      Basically, electrons do not follow circular orbits, but they have some probability of being found in some places. Synchrotron radiation only applies to classical pointlike particles moving in a path

    • Photo: Clare Burrage

      Clare Burrage answered on 15 Mar 2012:

      That’s a great question, and like Mario says it’s the question that led to the development of quantum mechanics. We can’t understand why electrons don’t spin into the centre of the nucleus without quantum physics.
      Quantum mechanics tells us that the electrons in an atom can’t have any amount of energy they want, instead the energy they can have comes in fixed amounts or packets (called quanta). The electrons have to have at least one of these packets, and so they can’t lose all their energy, which they would do if they spun into the center of the nucleus.

    • Photo: Elizabeth Pearson

      Elizabeth Pearson answered on 16 Mar 2012:

      Good question and yup, it’s quantum mechanics. A lot of things that never made sense at first can be explained by quantum. Anything really small starts involving quantum mechanics. The problem is we find it hard to connect the really small to the really big. It can get annoying sometimes. You spend ages working with one theory and then realise that you need to add in the other to get it to work and it just won’t go!

      There’s a series of books I read (Discworld) where anything that can’t be explained is put down to ‘because of quantum’. Sometimes it does seem like that.

Comments

  • Photo: sebstrug

    sebstrug commented on :

    I am aware of their existence in terms of probability, however wouldn’t this just mean that there is no force (such as the centrifugal one) keeping them near the nucleus, therefore why would they not collapse into the centre? How are these quanta preventing this collapse? I am a bit confused. Do you mean that the strong force prevents this?

    Thank you very much for your detailed answers 🙂