Energy in physics feels analogous to money in economics. Is a manmade medium of exchange used for convenience. It is the exchange medium between measureable physical states/things.
Is energy is real in the same way money is? An incredibly useful accounting trick that is used so frequently it feels fundamental, but really it’s just a mathmatical convenience?
Small aside: From this perspective ‘conservatipn of energy’ is a redundant statement. Of course energy must be conserved or else the equations are wrong. The definition of energy is it’s conservation.
Acoustic waves propagating through a medium (air) exist regardless of whether or not something can perceive it as audio. I would argue that the mechanical phenomenon we call “sound” (acoustic waves) exists regardless of whether or not someone hears it. Similar to how light (electromagnetic radiation) exists regardless of if someone is around to look at it.
That saying always seemed really stupid to me. Of course it makes a sound. Ugh