Physics emerged from the generality of “natural sciences” comparatively recently; it slept long among them until a few centuries ago it exploded producing a host of discoveries and notions that changed drastically the world and our way of life – for better or worse, hard to say. Still even today there’s no sharp border between it and chemistry, biology and – believe it or not – philosophy, thus deciding what belongs in this category is by necessity somewhat arbitrary. Anyway, as a general criterion, if it’s about science but isn’t sticky, doesn’t wriggle and doesn’t stink, here is where you can find it.