Photography using fast shutter speeds fascinates me. There are physical issues like getting the shutter to move fast enough as well as lighting considerations which are interesting on their own. But what gets me is that you can take an image that's 1/5000th of a second and know not only that this moment was unique among five thousand other images in that single second, but that the moment could also be broken down another 5,000 times, or 5,000 multiplied by 5,000 times more than that. So much goes by in our lives that we never perceive without some form of electronic assistance.
In this case, I've captured cavitation bubbles in some alder-smoked tomato soup I made for my wife. These bubbles are formed in the liquid due to the rapid movement of the food processor blade. The blade moves so fast its pressure upon the liquid forms a cavity: a tiny void space that collapses in on itself in less than 1,000th of a second. The collapse sets up a pressure wave. The waves compound to make vibrations. Strong vibrations create undue noise and can wreck machinery. Underwater propellers like those found on boats or submarines will have designs that reduce cavitation.
In the case of tomato soup, cavitation helps break up bits of food that aren't smooth. My wife likes her soup to be silky smooth. I add a little cream at the end to make it so.