While talking with a fellow 6.01 TA, I realized that almost all physical systems/phenomena I’ve studied can be described by a combination of impedance matching and feedback.
…Ok, feedback is not very surprising, it’s everywhere. But let’s talk about impedance matching.
Any electromagnetic systems involve impedance matching…from transmission lines, to optical refraction/reflection, to radio waves, to lasers.
Mechanical systems can be solved by generalizing impedance matching as well. By modeling bodies as coupled springs, the spring constant then become the analog of the EM ‘impedance’. Friction even, can be seen as the result of mismatching impedance between the surfaces.
I don’t have too much knowledge about biological systems, but the first thing that comes to mind is the immune system reacts to mismatch of the antigens (not my best analog but eh…).
Upon further thought, this seemingly surprising revelation becomes an inevitable result of the fact that every physical thing is made of matter…atoms (as far as this argument is concerned). Because different atoms have different masses, electrical properties, they form different substances which result in different reaction to energy. This difference in the propagation of energy thus results in the various impedance matching phenomena.
So we come to a sort of non-conclusion…all physical phenomena are derived from interactions of matter and energy. Brilliant!