What Happens Inside the Atom - Electrons and the Quantum World
Our conception of the atom has undergone many changes since the day the idea that matter consisted of indivisible particles was first floated by the Indians and Greeks. However it is only in this century that we have come to know something of what truly goes on inside the atom. We are all by now familiar with the iconic picture of an atom - a circle with a couple of little circles whizzing around it, rather like the moon orbits the earth. In the case of the atom, the 'earth' is called the nucleus and the 'moons' are called electrons. What keeps the electrons hanging around the nucleus? Well, if you remember the old adage 'like charges repel, unlike attract': electrons have a negative charge, and the nucleus has a positive charge. The flipside of this is that the electrons need energy if they are to avoid spiralling into the nucleus. This was one of the main questions at the beginning of the century: where does this energy come from? The answer turns out to ...