
Speaker: Marius Lemm
Title: Why doesn't an electron fall into the nucleus
Abstract:
In physics class at school, we are taught that matter is composed of atoms. We learn that every atom has at
its center a positivelycharged nucleus, around which negativelycharged electrons orbit, just like
planets orbiting the sun. However, we also learn that positive and negative charges attract. So, ... why
doesn't an electron simply fall into the nucleus? This is no small question as the answer holds the
key to the stability of all matter around us. It turns out that the answer lies in quantum mechanics.
This lecture will give a crash course on the mathematics describing quantum mechanics and in particular
pin down the notion of "uncertainty principle" mathematically. It will conclude with a proof that a
quantummechanical electron does not fall into the nucleus, hopefully prompting a sigh of relief
from the audience.
