Section 6.1 Introduction
We have encountered already a number of peculiar features of quantum mechanics such as wave-particle duality, spatially spread out states, and point particles with nonzero spin angular momentum. Now we are going to add another peculiar feature called quantum indistinguishability that arises when we make the step up from one particle to two particles.
What we will see is that quantum particles are indistinguishable in a way that classical particles cannot be. And this indistinguishability has very real consequences, ranging from lasers to superconductors to white dwarfs. Most importantly, it is this indistinguishability of quantum particles that leads to the periodic table and the chemical properties of the elements, which, needless to say, play a pretty big role in our everyday existence.