We receive feedback in multiple forms - be it through academics, sports, relations, music, social media, you name it - there’s a whole bunch of examples one can find in any field that involves feedback of some sort.

There’s a specific understanding of what feedback is in a technical sense and a whole lot of theory and math surround it. Having had a bunch of specialization courses in control systems through my education, I can guarantee that there’s a lot going on under the hood than simply saying “oh, let’s close the loop and update our values to meet our setpoints.”

Specifically, in control theory, there’s so much more to consider that one may lose their path quite easily in all the math involved (or even some of the theoretical aspects). For instance, think about the time factor - too late to respond to an input and you may end up doing more harm than good by providing a positive feedback instead of negative - but in some cases, a positive feedback is desired for sustained oscillations (as expressed using the Barkhausen criterion).

And this is just one simple example. There are a lot of ways in which you can analyze a given system, and a lot of ways in which you can formulate the system itself. Mathematically unmodelled systems can be “identified” using some heuristics. Known systems can be reduced by certain mathematical tricks.

It’s so interesting. And what makes it all the more fascinating is the fact that there are examples in very varied places. The stock market can be considered a feedback system, for instance - there are sellers and buyers constantly wanting to meet some targets and the market responds to the collective sentiment of everyone involved - and at times it may go unstable as seen during the subprime mortgage crisis or the Great Depression in which a massive input may be needed from the government.

But it’s not all too difficult to conceive - we see it around us fairly easily. What blew my mind was an example I came across through my courses - a feedback system involving populations of rabbits and wolves in a forest! If the rabbit population goes up, there is an opportunity for wolves to get food and increase in number - but too many wolves and you have starvation because of a limited number of rabbits, thus seeing a dwindling number of wolves - until there are too many rabbits again through procreation, and so on. There are nice simulations that can be run online!

Feeback systems are really interesting, with(out) the math.