We really should have started with some fancy quote, spoken in the past, and reverberating into the ages to come. But we didn’t. So let’s start instead with a small experiment. Fill a cup with something. No, not coffee, we know you were thinking about it. Something clear. You need to see through it. You also need to have some little pieces of something floating homogeneously around in your cup, like chia seeds once they are really squishy, or that weird aloe drink they sell at the supermarket. The latter, in fact, proves to be the best for this experiment.
Everybody's physics
Many Body Physics 