Why do electrons not fall into the nucleus of an atom?

The picture of electrons "orbiting" the nucleus like planets around the sun remains an enduring one, not only in popular images of the atom but also in the minds of many of us who know better. read more

What this means is that within the tiny confines of the atom, the electron cannot really be regarded as a "particle" having a definite energy and location, so it is somewhat misleading to talk about the electron "falling into" the nucleus. read more

In this view, it appears as if the electron does fall into the nucleus! According to classical mechanics, the electron would simply spiral into the nucleus and the atom would collapse. Quantum mechanics is a different story. read more

That's what should happen if electrons fell into a nucleus. A proton's mass is 1.6726 x 10-27 kg, and an electron's mass is 0.00091 x 10-27 kg, but a neutron's mass is 1.6749 x 10-27 kg. So the mass of an electron and proton combined is still nowhere near enough for a neutron. read more